STOCK TITAN

TPST-2003 delivers 100% CRs in rrMM, Tempest (NASDAQ: TPST) says

Filing Impact
(Moderate)
Filing Sentiment
(Neutral)
Form Type
8-K

Rhea-AI Filing Summary

Tempest Therapeutics furnished an investor presentation and press release outlining updated clinical data for its lead dual-targeting CAR-T candidate TPST-2003.

Across two ongoing Phase 1/2 trials in relapsed/refractory multiple myeloma and POEMS syndrome, all 15 CAR-T-naïve efficacy-evaluable patients achieved complete responses. In REDEEM-1, 10 of 10 CAR-T-naïve multiple myeloma patients reached complete response using standard IMWG criteria. In POEMS-1, all five efficacy-evaluable patients achieved complete VEGF-based responses within two months of treatment.

Including a prior investigator-initiated trial, 44 patients have received TPST-2003. Among 29 CAR-T-naïve evaluable multiple myeloma patients with measurable disease at baseline, the overall response rate was 100%, with a median progression-free survival of 23.1 months across 24 patients and the same median in those with extramedullary disease. The safety profile showed no grade ≥3 cytokine release syndrome or ICANS in REDEEM-1, though four deaths occurred in the IIT, including two therapy-related pneumonias and two from disease progression. Tempest states these results support its objective of meeting with the FDA to discuss a potential U.S. registrational study for TPST-2003 later in 2026.

Positive

  • Exceptionally strong early efficacy for TPST-2003, with a reported 100% complete response rate in 15 CAR-T-naïve efficacy-evaluable patients across REDEEM-1 and POEMS-1 and a 100% overall response rate among 29 CAR-T-naïve multiple myeloma patients with measurable disease at baseline.

Negative

  • Safety and durability uncertainties remain, as total exposure is limited to 44 treated patients and the investigator-initiated trial reported four deaths, including two attributed to therapy-related pneumonia and two from disease progression.

Insights

Early TPST-2003 data show striking responses but remain small and preliminary.

Tempest Therapeutics reports that its dual-target CD19/BCMA CAR-T, TPST-2003, produced a 100% complete response rate in 15 CAR-T-naïve efficacy-evaluable patients across two Phase 1/2 studies in relapsed/refractory multiple myeloma and POEMS syndrome.

Including a prior investigator-initiated trial, 29 CAR-T-naïve multiple myeloma patients with measurable disease at baseline achieved a 100% overall response rate and median progression-free survival of 23.1 months, including those with extramedullary disease, a historically difficult subgroup. REDEEM-1 also reported no grade ≥3 cytokine release syndrome or ICANS, suggesting a favorable acute safety profile.

However, total exposure remains limited at 44 treated patients, and four deaths were seen in the IIT, including two therapy-related pneumonias and two from disease progression. The company’s stated objective to meet the FDA about a potential U.S. registrational study later in 2026 will depend on how durability and safety look as follow-up matures and enrollment progresses.

Item 7.01 Regulation FD Disclosure Disclosure
Material non-public information disclosed under Regulation Fair Disclosure, often investor presentations or guidance.
Item 8.01 Other Events Other
Voluntary disclosure of events the company deems important to shareholders but not covered by other items.
Item 9.01 Financial Statements and Exhibits Exhibits
Financial statements, pro forma financial information, and exhibit attachments filed with this report.
CAR-T-naïve complete response rate 100% (15/15 patients) Efficacy-evaluable CAR-T-naïve patients across REDEEM-1 and POEMS-1
REDEEM-1 complete responses 10/10 patients CAR-T-naïve rrMM patients, IMWG uniform response criteria
Overall response rate in rrMM 100% (29/29 patients) CAR-T-naïve evaluable rrMM patients with measurable disease at baseline
Median progression-free survival 23.1 months 24 rrMM patients in investigator-initiated trial, including extramedullary disease
Patients treated with TPST-2003 44 patients Combined across IIT, REDEEM-1, and POEMS-1 trials
Grade ≥3 CRS and ICANS in REDEEM-1 0 events No grade ≥3 cytokine release syndrome or ICANS reported
Deaths in IIT 4 deaths Two therapy-related pneumonias and two from disease progression
Target enrollment for REDEEM-1 and POEMS-1 44 patients (32 + 12) Planned totals for REDEEM-1 and POEMS-1 TPST-2003 trials
chimeric antigen receptor T-cell medical
"its lead dual-targeting chimeric antigen receptor T-cell (“CAR-T”) therapy product candidate, TPST-2003"
Chimeric antigen receptor T-cell (CAR T-cell) therapy engineers a patient’s own immune cells to recognize and attack specific cancer markers by adding a synthetic receptor; think of it as giving soldiers new, high-precision binoculars to spot hidden targets. It matters to investors because CAR T therapies can offer powerful, sometimes one-time treatments that command premium pricing, drive biotech valuations, and carry risks and costs tied to manufacturing, safety and regulatory approval.
extramedullary disease medical
"including patients with extramedullary disease. The REDEEM-1 trial has a targeted full enrollment"
Extramedullary disease means cancer cells have spread and are growing outside the bone marrow, where certain blood cancers normally live. Like weeds appearing beyond a fenced garden, this spread can make the disease harder to treat, change which medicines or procedures are needed, and affect outcomes, clinical trial results, and costs—information investors watch because it can influence a company’s revenue, regulatory decisions, and stock value.
progression-free survival medical
"Median PFS of 23.1 months across all patients (24/24), median PFS of 23.1 months in EMD patients"
Progression-free survival is the length of time during and after a treatment that a patient's disease does not get worse, measured from the start of treatment until the disease shows measurable signs of progression or the patient dies. Investors care because longer progression-free survival in clinical trials often signals that a drug is effective, improving chances of regulatory approval, market adoption, and revenue potential—think of it as a stopwatch showing how long a therapy can keep the illness at bay.
cytokine release syndrome medical
"The observed safety profile (no Grade >3 CRS or ICANS), together with the consistency of responses"
An intense immune overreaction in which the body's defense system releases a large surge of signaling proteins, causing fever, low blood pressure, breathing trouble or organ stress; imagine the immune system's alarm going into overdrive and flooding the body with emergency responders. Investors care because this side effect can slow or block regulatory approval, increase clinical trial costs and liabilities, limit how widely a therapy can be used, and therefore affect a drug's market value and sales potential.
immune effector cell-associated neurotoxicity syndrome medical
"no Grade >3 CRS or ICANS), together with the consistency of responses observed in the REDEEM-1 trial"
immune effector cell-associated neurotoxicity syndrome (ICANS) is a brain-related side effect that can occur after treatments that activate powerful immune cells, such as engineered cell therapies. It can cause confusion, speech problems, seizures or coma when the immune response unintentionally harms brain function; think of an overenthusiastic security system that starts damaging the house it’s protecting. Investors care because ICANS affects clinical trial results, regulatory approvals, product labeling, treatment adoption, monitoring costs and potential liability, all of which influence a therapy’s commercial value.
investigator-initiated trial clinical
"a prior Phase 1/2 investigator-initiated trial (“IIT”) evaluating TPST-2003 in rrMM"
A clinical study led and managed by an independent researcher or physician rather than the company that makes the drug or device; the investigator designs the protocol, runs the study at their site(s), and often controls the data even if the company supplies the product or funding. For investors, these trials can produce important third‑party validation or new uses for a product — like an independent test drive revealing strengths or limits — and their outcomes can change a product’s commercial and regulatory prospects.
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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

 

 

FORM 8-K

 

 

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 6, 2026

 

 

Tempest Therapeutics, Inc.

(Exact name of Registrant as Specified in Its Charter)

 

 

 

Delaware   001-35890   45-1472564
(State or Other Jurisdiction
of Incorporation)
 

(Commission

File Number)

  (IRS Employer
Identification No.)

 

2000 Sierra Point Parkway, Suite 400  
Brisbane, California   94005
(Address of Principal Executive Offices)   (Zip Code)

Registrant’s Telephone Number, Including Area Code: (415) 798-8589

 

(Former Name or Former Address, if Changed Since Last Report)

 

 

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

 

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

 

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

 

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

 

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

 

Title of each class

 

Trading
Symbol(s)

 

Name of each exchange
on which registered

Common Stock, $0.001 par value   TPST   The Nasdaq Stock Market LLC
Series A Junior Participating Preferred Purchase Rights   N/A   The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company 

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

 

 
 


Item 7.01

Regulation FD Disclosure

On May 6, 2026, Tempest Therapeutics, Inc. (the “Company”) posted an updated corporate presentation, dated May 6, 2026, to the “News, Events & Presentations” subsection of the “Investors” tab on the Company’s website at www.tempesttx.com.

The information furnished in this Item 7.01 (including Exhibit 99.1) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act or the Exchange Act, except as expressly provided by specific reference in such a filing.

 

Item 8.01

Other Events

On May 6, 2026, the Company issued a press release entitled “Tempest Presents Clinical Update at ISCT 2026 Annual Meeting.” A copy of the Company’s press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

 

Item 9.01

Financial Statements and Exhibits

(d) Exhibits.

 

Exhibit
No.
   Description
99.1    Press release, dated May 6, 2026
99.2    Corporate Presentation dated May 2026
104    Cover Page Interactive Data File (embedded within the Inline XBRL document)

 


SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

 

      TEMPEST THERAPEUTICS, INC.
Date: May 6, 2026     By:  

/s/ Nicholas Maestas

    Name:   Nicholas Maestas
    Title:   Chief Financial Officer

Exhibit 99.1

 

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Tempest Presents Clinical Update at ISCT 2026 Annual Meeting

 

   

100% complete response (“CR”) rate among all 15 CAR-T-naïve efficacy evaluable patients treated with TPST-2003 dual-targeting CD19/BCMA CAR-T across two ongoing Phase 1 trials (REDEEM-1 and POEMS-1)

 

   

Favorable safety profile with no Grade >3 CRS or ICANS in REDEEM-1 trial evaluating TPST-2003 in relapsed/refractory multiple myeloma (rrMM)

 

   

100% CR as measured by normalization of serum vascular endothelial growth factor levels (“CRVEGF“) rate among all five efficacy evaluable patients in POEMS-1 trial evaluating TPST-2003 in the rare disease, POEMS syndrome

 

   

44 patients treated to date across three studies

 

   

Results support clinical benefit of parallel-structure dual-targeting CAR architecture in patients with rrMM, including in patients with extramedullary disease (“EMD”)

 

   

Median progression free survival of 23.1 months, including in patients with EMD, if replicated in registrational trial, would position TPST-2003 as potentially class-leading therapy for rrMM

Brisbane, CA, May 6, 2026 Tempest Therapeutics, Inc. (Nasdaq: TPST) (“Tempest”) today presents its most recent clinical data from its lead dual-targeting chimeric antigen receptor T-cell (“CAR-T”) therapy product candidate, TPST-2003, at the International Society for Cell & Gene Therapy (“ISCT”) Scientific Annual Meeting in Dublin, Ireland. Updates include the latest data from the ongoing REDEEM-1 Phase 1/2a trial evaluating TPST-2003, as well as progress in Tempest’s other dual-targeting CAR-T pipeline programs.

Earlier this year, Tempest announced positive interim data from REDEEM-1, including a 100% complete response (“CR”) rate among all six efficacy then-evaluable patients according to the International Myeloma Working Group (“IMWG”) uniform response criteria, as well as a favorable safety profile. Today’s clinical update more than doubles the previous dataset, achieving a 100% CR rate among all 15 CAR-T-naïve efficacy evaluable patients across two ongoing Phase 1 trials – REDEEM-1 evaluating TPST-2003 in relapsed/refractory multiple myeloma (“rrMM”) (10/10 according to the IMWG uniform response criteria) and POEMS-1 evaluating TPST-2003 in POEMS syndrome (5/5 CRVEGF).


To date, a total of 44 patients have received one infusion of TPST-2003, including 24 patients in a prior Phase 1/2 investigator-initiated trial (“IIT”) evaluating TPST-2003 in rrMM, 13 patients in the ongoing REDEEM-1 trial, and seven patients in the ongoing POEMS-1 trial, representing one of the largest datasets evaluating a CD19/BCMA dual-targeting CAR-T therapy.

All 10 CAR-T-naïve patients currently evaluable for efficacy in the REDEEM-1 trial – three treated at dose level 1 (1 x 106 cells/kg), three at dose level 2 (2 x 106 cells/kg), and four at dose level 3 (3 x 106 cells/kg) – achieved a CR according to the IMWG uniform response criteria. A single patient, who had previously received a BCMA-targeting CAR-T, did not respond. Among 29 CAR-T-naïve evaluable patients with measurable disease at baseline across REDEEM-1 and the prior Phase 1/2 IIT, including 18 patients with EMD, the overall response rate (“ORR”) was 100% (29/29) according to the IMWG uniform response criteria.

In the POEMS-1 trial, as of the January 31, 2026 data cutoff, all five evaluable patients had achieved a CRVEGF within two months of being administered TPST-2003. No dose-limiting toxicities were observed in any of the treated patients.

“The results that we are presenting at ISCT this week support our belief that TPST-2003 could offer a life-saving option for patients with rrMM, and, if approved, may outperform first-generation single-targeting CAR-T therapies, in particular in patients with EMD” said Dr. Matt Angel, President and Chief Executive Officer of Tempest. “We are excited by the potential to offer patients who have relapsed from multiple prior lines of therapy a treatment that may achieve up to complete remission of their cancer.”

The observed safety profile (no Grade >3 CRS or ICANS), together with the consistency of responses observed in the REDEEM-1 trial continue to support Tempest’s plan to pursue its objective of meeting with the FDA to discuss initiating a U.S. registrational study later this year.

Presentation Details

REDEEM-1, a multicenter open-label Phase 1/2a study of a BCMA/CD19 dual-targeting CAR-T therapy in patients with relapsed/refractory multiple myeloma including those with extramedullary disease. Abstract #1268. Oral Presentation, May 6, 2026 (12:00-13:00 GMT) & Poster Reception, May 7, 2026 (18:00-19:30 GMT), Immunotherapy Session. Presenter: Dr. Matt Angel.


About TPST-2003

TPST-2003 is an autologous CD19/BCMA dual-targeting CAR-T therapy designed to improve response depth and durability in patients with relapsed/refractory multiple myeloma (“rrMM”) through a parallel dual-targeting CAR structure designed to address tumor heterogeneity and antigen escape. TPST-2003 is being developed in China by Tempest’s partner, Novatim Immune Therapeutics (“Novatim”). Under its agreement with Novatim, Tempest has the exclusive right to develop TPST-2003 outside of China, India, Turkey, and Russia.

About REDEEM-1

REDEEM-1 (Study nos. CTR20233309/NCT06223646) is a Phase 1/2a clinical trial evaluating TPST-2003 in patients with relapsed/refractory multiple myeloma, including patients with high-risk cytogenetics and patients with extramedullary disease. The REDEEM-1 trial has a targeted full enrollment of 32 patients. The REDEEM-1 trial is sponsored and being conducted by Tempest’s partner, Novatim Immune Therapeutics, with a total of eight clinical sites registered in China: Peking Union Medical College Hospital (Dr. Jian Li; lead site), The First Affiliated Hospital of Nanchang University (Dr. Fei Li), Peking University First Hospital (Dr. Yujin Dong), Henan Cancer Hospital (Dr. Baijun Fang), Shanxi Provincial Cancer Hospital (Dr. Liping Su), The Second Xiangya Hospital of Central South University (Dr. Hongling Peng), The First Affiliated Hospital of China Medical University (Dr. Xiaojing Yan), and The Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College (Dr. Dehui Zou).

About POEMS-1

POEMS-1 is a Phase 1 clinical trial (Study nos. CTR20242409/NCT06518876) evaluating TPST-2003 in patients with POEMS, a rare blood disorder caused by abnormal plasma cells. The POEMS-1 trial has a targeted full enrollment of 12 patients. The POEMS-1 trial is sponsored and being conducted by Tempest’s partner, Novatim, with a total of three clinical sites registered in China: Peking Union Medical College Hospital (Dr. Jian Li; lead site), Xuanwu Hospital Capital Medical University (Dr. Wanling Sun), and West China Hospital, Sichuan University (Dr. Yu Wu).


Additional Clinical Trial Evaluating TPST-2003

A Phase 1/2 IIT (Study no. NCT04714827) is evaluating TPST-2003 in patients with relapsed/refractory multiple myeloma, including patients with high-risk cytogenetics and patients with extramedullary disease. The IIT is sponsored and being conducted by Tempest’s partner, Novatim, with a total of two clinical sites registered in China: Shanghai Fourth People’s Hospital (Dr. Weijun Fu; lead site) and Shanxi Provincial Cancer Hospital (Dr. Liping Su).

About Tempest Therapeutics

Tempest Therapeutics is a clinical-stage biotechnology company developing a pipeline of advanced CAR-T cell therapy product candidates to treat cancer. Tempest is headquartered in Brisbane, California. More information about Tempest can be found on the company’s website at https://www.tempesttx.com.

Forward-Looking Statements

This press release contains forward-looking statements (including within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended, and Section 27A of the Securities Act of 1933, as amended, concerning Tempest Therapeutics, Inc. These statements may discuss goals, intentions, and expectations as to future plans, trends, events, results of operations or financial condition, or otherwise, based on current beliefs of the management of Tempest Therapeutics, as well as assumptions made by, and information currently available to, management of Tempest Therapeutics. Forward-looking statements generally include statements that are predictive in nature and depend upon or refer to future events or conditions, and include words such as “may,” “will,” “should,” “would,” “could”, “expect,” “anticipate,” “plan,” “likely,” “believe,” “estimate,” “project,” “intend,” “goal”, “suggest”, “target” and other similar expressions. All statements that are not historical facts are forward-looking statements, including but not limited to, statements regarding: Tempest Therapeutics’ plan to present data from clinical trials, including the REDEEM-1 trial and the POEMS-1 trial; the design, initiation, progress, timing, scope and results of clinical trials; the planned advancement of a diversified next-generation CAR-T pipeline; anticipated therapeutic benefit and regulatory development of Tempest Therapeutics’ product candidates, including TPST-2003; Tempest Therapeutics’ ability to achieve its operational plans, and Tempest’s plan to pursue its objective of meeting with the FDA to discuss initiating a U.S. registrational study later this year. All forward-looking statements in this press release are based on Tempest Therapeutics’ current expectations, estimates and projections about its industry as well as management’s current beliefs and expectations of future events only as of today and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in or implied by such forward-looking statements. These risks and uncertainties include, but are not limited to Tempest


Therapeutics’ need for additional capital to fund its planned programs and operations and to continue to operate as a going concern; unexpected safety or efficacy data observed during preclinical or clinical trials; the possibility that results from prior clinical trials and preclinical studies may not necessarily be predictive of future results; past results may not be indicative of future results; clinical trial site activation or enrollment rates that are lower than expected; loss of key personnel; changes in expected or existing competition; changes in the regulatory environment; risks relating to volatility and uncertainty in the capital markets for biotechnology companies; and unexpected litigation or other disputes. These and other factors that may cause actual results to differ from those expressed or implied are discussed in greater detail in the “Risk Factors” section of Tempest Therapeutics’ Annual Report on Form 10-K for the year ended December 31, 2025, filed with the Securities and Exchange Commission (“SEC”) on March 30, 2026, and in other documents filed by Tempest Therapeutics from time to time with the SEC. Except as required by applicable law, Tempest Therapeutics undertakes no obligation to revise or update any forward-looking statement, or to make any other forward-looking statements, whether as a result of new information, future events or otherwise. These forward-looking statements should not be relied upon as representing Tempest Therapeutics’ views as of any date subsequent to the date of this press release and should not be relied upon as prediction of future events. In light of the foregoing, investors are urged not to rely on any forward-looking statement in reaching any conclusion or making any investment decision about any securities of Tempest Therapeutics.

Investor Contacts:

Sylvia Wheeler

Wheelhouse Life Science Advisors

swheeler@wheelhouselsa.com

Aljanae Reynolds

Wheelhouse Life Science Advisors

areynolds@wheelhouselsa.com

Exhibit 99.2

 

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® Developing Advanced Therapies for Cancer Patients


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Forward Looking Statements This presentation contains forward-looking statements (including within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended, and Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) concerning Tempest Therapeutics, Inc. (“Tempest Therapeutics”). These statements may discuss goals, intentions and expectations as to future plans, trends, events, results of operations or financial condition, or otherwise, based on current beliefs of the management of Tempest Therapeutics, as well as assumptions made by, and information currently available to, management of Tempest Therapeutics. Forward-looking statements generally include statements that are predictive in nature and depend upon or refer to future events or conditions, and include words such as “may,” “will,” “should,” “would,” “could”, “expect,” “anticipate,” “plan,” “likely,” “believe,” “estimate,” “project,” “intend,” and other similar expressions. All statements that are not historical facts are forward-looking statements, including any statements regarding: the potential benefits of Tempest Therapeutics’ expanded oncology pipeline; the design, initiation, progress, timing, scope and results of clinical trials; the anticipated therapeutic benefit, opportunity to improve patient care, and regulatory development of Tempest Therapeutics’ product candidates; Tempest Therapeutics’ ability to deliver on potential value-creating milestones; the potential use of Tempest Therapeutics’ product candidates to treat additional indications; Tempest Therapeutics’ ability to achieve its operational plans; and the sufficiency of Tempest Therapeutics’ cash and cash equivalents. Forward-looking statements are based on current beliefs and assumptions that are subject to risks and uncertainties and are not guarantees of future performance. Actual results could differ materially from those contained in any forward-looking statement as a result of various factors, including, without limitation: Tempest Therapeutics’ strategies, prospects, plans, expectations or objectives for future operations; the progress, scope or timing of the development of Tempest Therapeutics’ product candidates; the benefits that may be derived from any future products or the commercial or market opportunity with respect to any of Tempest Therapeutics’ future products; unexpected safety or efficacy data observed during preclinical or clinical trials; the possibility that results from prior clinical trials and preclinical studies may not necessarily be predictive of future results; past results may not be indicative of future results; clinical trial site activation or enrollment rates that are lower than expected; loss of key personnel; changes in expected or existing competition; changes in the regulatory environment; risks relating to volatility and uncertainty in the capital markets for biotechnology companies; unexpected litigation or other disputes; Tempest Therapeutics’ ability to protect its intellectual property rights; Tempest Therapeutics’ need for additional capital to fund its planned programs and operations and to continue to operate as a going concern; Tempest Therapeutics’ anticipated operations, financial position, ability to raise capital to fund operations, revenues, costs or expenses; statements regarding future economic conditions or performance; statements of belief and any statement of assumptions underlying any of the foregoing. These and other factors that may cause actual results to differ from those expressed or implied are discussed in greater detail in the “Risk Factors” section of the company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (SEC) on March 30, 2026, as well as in other filings the company may make with the SEC in the future. Except as required by applicable law, Tempest Therapeutics undertakes no obligation to revise or update any forward-looking statement, or to make any other forward-looking statements, whether as a result of new information, future events or otherwise. These forward-looking statements should not be relied upon as representing Tempest Therapeutics’ views as of any date subsequent to the date of this press release and should not be relied upon as prediction of future events. In light of the foregoing, investors are urged not to rely on any forward-looking statement in reaching any conclusion or making any investment decision about any securities of Tempest Therapeutics. This presentation discusses product candidates that are under clinical study and which have not yet been approved for marketing by the U.S. Food and Drug Administration. No representation is made as to the safety or effectiveness of these product candidates for the use for which such product candidates are being studied. This presentation incorporates publicly-available third-party data that Tempest Therapeutics has not independently verified. There are risks inherent in conducting cross-trial comparisons and the results should be interpreted with caution. The presentation of such third-party data does not represent a head-to-head comparison of how TPST-2003 performed against any other third-party drug candidate or study. Rather, such third-party data has been pulled by us from publicly-available sources for supplemental informational purposes, only. Tempest Therapeutics cautions you that any comparisons against third-party data set forth herein should not be viewed as a side-by-side comparison, and you should not rely on the completeness or accuracy of Tempest Therapeutics’ presentation of the results of any third-party drug candidate in these slides, due to differences in study design, how other companies quantify or qualify eligibility criteria, and how results are recorded, among other distinguishing factors and uncertainties. Because Tempest Therapeutics may be unaware of or may not adequately present various distinguishing factors and uncertainties, the comparisons set forth herein may not properly present such third-party data, which may differ materially from the data as presented here. Investors are encouraged to independently review third party data and should not rely on Tempest Therapeutics’ presentation of such data (including any such data placed in comparison with the performance of TPST-2003) as a single measure to evaluate Tempest Therapeutics’ business. The trademarks included herein are the property of the owners thereof and are used for reference purposes only. Such use should not be construed as an endorsement of such products.


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Selected Potential Value-Inflecting Milestones through Q4 2027 2026 2027 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Phase 1/2 IIT REDEEM-1 Phase 2b (China TPST-2003 results and Phase 2a registrational) REDEEM-1 Tech transfer enrollment start Phase 2b (China) CD19/BCMA Dual CAR-T Phase 2b (U.S. Phase 1/2a enrollment start complete File IND (U.S.) (China File BLA r/r Multiple Myeloma registrational) (China) interim registrational) interim data (China) with EMD data POEMS-1 Pre-IND (U.S.) interim data Phase 2b (U.S. and POEMS Syndrome Tech transfer Phase 1 (China) registrational) start interim data enrollment start Toxicology Phase 1/2 IIT Phase 1/2a TPST-2206 complete Phase 1/2 IIT (China) Phase 1/2 IIT (China) CD70/CD70 Dual CAR-T GMP (China) interim enrollment (China) results enrollment Renal Cell Carcinoma manufacturing data start start start TPST-3003 Phase 1/2 IIT Phase 1/2 IIT Phase 1/2a GMP Phase 1/2 IIT (China) Universal CD19/BCMA (China) (China) results enrollment start manufacturing (China) interim Dual CAR-T enrollment start data Phase 1 (U.S.) start File IND (U.S.) r/r Multiple Myeloma enrollment start TPST-4003 Phase 1/2 IIT Phase 1/2 IIT Phase 1 (U.S.) In vivo CD19/BCMA (China) (China) interim File IND (U.S.) enrollment Dual CAR-T enrollment data start SLE start All activities shown above in bold are 100% funded by strategic partner


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TPST-2003 Dual Targeting CD19/BCMA CAR-T


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TPST-2003 CD19/BCMA CAR-T TPST-20031,2 is the world’s first parallel-structure dual-target CAR-T cell therapy for rrMM with EMD & POEMS syndrome • REDEEM-1 Phase 1/2a (rrMM) and POEMS-1 Phase 1 (POEMS syndrome) Dual-target CAR-T structure • 44 patient target – 32 in REDEEM-1 and 12 in POEMS-1 • 20 patients dosed as of May 6, 2026 – 13 in REDEEM-1, 7 in POEMS-1 • 100% CR rate among CAR-T-naïve patients (15/15) – REDEEM-1 (10/10 CR) and POEMS-1 (5/5 CRVEGF) efficacy-evaluable as of March 31, 2026 and January 31, 2026, respectively • No grade ≥3 CRS, no grade ≥3 ICANS in REDEEM-1, Phase 1 enrollment complete (12/12), Phase 2a currently enrolling, first patient dosed May 2, 2026 • Phase 1/2 Investigator-Initiated Trial (rrMM) – Enrollment complete (24 patients) • 100% ORR among all 19 patients with measurable disease at baseline, 89.5% CR rate (17/19), 100% CR rate at highest dose level (5/5) • Median PFS of 23.1 months across all patients (24/24), median PFS of 23.1 months in EMD patients (15/15) • All evaluable patients at month 12 were MRD-negative (5/5) 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory Multiple Myeloma Including Those with Extramedullary Disease”. Blood 144 (2024) 923- 924., 2Li, J., et. al. “REDEEM-1, A MULTICENTER OPEN-LABEL PHASE 1/2A STUDY OF A BCMA/CD19 DUAL-TARGETING CAR-T THERAPY IN PATIENTS WITH RELAPSED/REFRACTORY MULTIPLE MYELOMA INCLUDING THOSE 6 WITH EXTRAMEDULLARY DISEASE”. Cytotherapy 28 (2026) 1268., Interim data update, May 6, 2026. “CRS” Cytokine Release Syndrome, “EMD” Extramedullary Disease, “CR” Complete Response, “CRVEGF” Complete Response as measured by normalization of serum vascular endothelial growth factor levels, “ORR” Overall Response Rate, “PFS” Progression-Free Survival, “ICANS” Immune effector cell-associated neurotoxicity syndrome, “MRD” Minimal Residual Disease.


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TPST-2003 Dual CAR-T for rrMM1: Study Design Multicenter, open label, IIT study FPI Jan.2021, LPI Jun.2024, Patients continued to be assessed for response Data cut-off Jul.25th,2024, Efficacy evaluable patients N=23, Safety Set N=20, PKPS N=20 Key Inclusion criteria Primary endpoint: Dose Level: • Relapsed/ Refractory Multiple • AE and SAE • DL 1: 1.0x106 CAR-T cells/kg Myeloma (R/R MM) • Clinical recommended dose • DL2: 2 .0 x 106 CAR-T cells/kg • R/R MM pts with ~1 prior lines of • DL3: 3.0x106 CAR-T cells/kg therapy including proteasome Secondary endpoint: inhibitor (Pl), and immunomodulatory • PK/PD drug (IMiDs), and/or anti-CD38 • PFS, ORR, DoR, OCR, OS ICF and Apheresis KQ-2003 QC Lymphodepletion KQ-2003 DLT Follow up Screening Manufacturing Release (Flu/Cy*3 days) Infusion Evaluation Assessment visits , , , ‘ ‘ ‘ ‘ ... ~ ‘ D-47 D-27 D-6 DO D1~ D28 M2 M3 MG M9 M12 M15 M18 M21 M24 PKPS : Pharmacokinetics Parameter Set; AE: Adverse Event; SAE: Serious Adverse Event; PFS: Progression Free Survival ; ORR: Objective Response Rate; DoR: Duration of Response; OCR: Disease Control Rate; OS: Overall Survival; ICF: Informed Consent Form ; QC: Quality control 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory ~TEMPEST 8 Multiple Myeloma Including Those with Extramedullary Disease”. Blood 144 (2024) 923-924. ~ THERAPEUT I CS


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TPST-2003 Dual CAR-T for rrMM1: Baseline Characteristics Baseline Characteristics Total {N=23) Baseline Characteristics Total {N=23) Median age Crange ) 64 (52-77) Median prior lines of therapy, n(%) 5 (2-11) Male, n(%) 12 (52.2) Prior auto-SCT, n(%) 9 (39.1) ECOG performance-status score, n(%) Refractory, n(%) ¦ 0 14 (60.9) ¦ Pl refractory 23 (100) ¦ 1 8 (34.8) 2 ¦ IMiD refractory 23 (100) ¦ 1 (4.3) ¦ Triple-refractory 21 (91.3) Type of myeloma, n(%) ¦ Quadru-refractory 16 (69.6) ¦ lgG 13 (56.5) ¦ Penta-refractory 6 (26.1) ¦ lgA 6 (26.1) ¦ lgD 1 (4.3) Extramedullary disease, n(%) 14 (60.9) ¦ Light chain 3 (13.0) Bridging therapy 18 (78.3) High-risk profile8 , n(%) 12/19c {63.2) Refractory to last therapy 18 (78.3) Double-hitb, n(%) 4/19 (21.1) a FISH By mSMART 3.0 b By presence two of del(17p), t(4;14),t(14;16),t(14;20),gain 1q, or p53 mutation c The rest 4 pts (all with EMO ) without clonal plama cells in BM at baseline for FISH analysis 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory ~TEMPEST 9 Multiple Myeloma Including Those with Extramedullary Disease”. Blood 144 (2024) 923-924.


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TPST-2003 Dual CAR-T for rrMM1: Hematological Response 01003 Hematological ORR* N=18 1 [ 02003 DL N=3 N=10 N=5 N=18 N=3 100% 02002 80% 01010 -02008 ~ 60% - 0 01011 CJ) 40% 0:: sCR 02011 20% 33.30% DL2 02015 CR N=11 0% 02013 1//////////////////////// .......  VGPR DL1 DL2 DL3 All Pts 02017 ¦ VGPR ¦ sCR/CR PR 02020 02019 SD MRD Assessment** N=20 02021 N= 18 N=11 N=5 Relapse after CR—100% 02023 Non hematological 0 ~ - 80% 02007 measurable indicators Q.) ro 02012 0:: 60% ¦ PD Q.) 02016 > 40% :;:; ¦ Death Ctl 02018 Ol DL3 Q.) 20% MRD-negative C N=9 02025 0 0% 0:: 02026 MRD-positive ~ M3 M6 M1 2 02027 ..... Ongoing ¦ M RD+ ¦ M RD- 02028 02029 •••► Survival fo llow-up *Pts had Hematological measurable indicators: N=18(18/23); **NGF Sensitivity: a threshold of 10-5 nucleated cells 0 3 6 9 12 15 18 21 24 27 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory Multiple Myeloma Including Those with ~TEMPEST Extramedullary Disease”. Blood 144 (2024) 923-924. “sCR” stringent complete response, “CR” complete response, “VGPR” very good partial response, “PR” partial response, “SD” stable disease, “PD” 10 ~ THERAPEUT I CS progressive disease, “MRD” minimal residual disease, “ORR” objective response rate, “Pts” patients


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TPST-2003 Dual CAR-T for rrMM1: EMD PET Response Hematological PET Response Of EMD Response PET ORR: 85.7% (12/14) N=1 N=7 N=6 N=14 DL1[ 02003—100% 02008—80% 02015—•••► 02013 0 -;,12_ 60% DL2 Cl) 02017 0.... 40% CMR 02020 PMR 20% 02019 •••► 02021 SMD 0% 02018 Hematologic PD DL 1 DL2 DL3 All Pts •••► ¦ 02025 ¦ SMD ¦ PMR ¦ CMR ¦ Death DL3 02026 02027 —► Ongoing Best Reduction Size 02028 •••► Survival follow-up of soft tissue plasmacytomas 02029 - 0 3 6 9 12 15 18 21 ——·-···-······-···-· ·-· ——·—···· ·-······ -75%~-100% TABLE 7. Proposed Refinement of PET Response Criteria After Therapy PET Response After 50% l Therapy Response Criteria Complete metabolic Uptake c;; liver activity in BM sites and Fls previously involved (including extramedullary and paramedullary response disease [DS score 1-3]) Partial metabolic Decrease in number and/or activity of BM/Fls present at baseline, but persistence of lesion(s) with uptake > liver response activity (DS score 4 or 5) -50% ~ -75% Stable metabolic disease No significant change in BM/Fls compared with baseline 14% Progressive metabolic New Fls compared with baseline consistent with myeloma disease Abbreviations: BM, bone marrow; DS, Deauville scale; FL, focal lesion; PET, positron emission tomography. Elena Zamagni, et al. J Clin Oneal. 2021 Jan 10;39(2):1 16-125. doi: 10.1200/JC0.20.00386 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory ~TEMPEST 12 Multiple Myeloma Including Those with Extramedullary Disease”. Blood 144 (2024) 923-924.


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TPST-2003 Dual CAR-T for rrMM1: EMD PET Response Case-02008 58-yo male Penta-refractory, 11 prior LOT Case-02003 55-yo female Quad-refractory, 5 prior LOT M3: VGPR & PMR -c, M6: sCR MRD- & CMR for 21 + mos M3: VGPR & CMR-c, M9: sCR MRD- & CMR for 23+ mos 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory ~TEMPEST 13 Multiple Myeloma Including Those with Extramedullary Disease”. Blood 144 (2024) 923-924. ~ THERAPEUT I CS


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TPST-2003 Dual CAR-T for rrMM1: Survival All EMO NonEJ.,D 100% 100% ~ 15% li 111, ~· 2’ ~ 50%, iii, 2 > ;;;J, (I), ,5~ staVmelfian=23.1(95%ct 13.7--:W,,) E:M D: ::::;u ( 9 s • 1: 6.a- ) NOfl- EM D : S.6 ( 9511GI : :?.07—) 0% 0% 0 3 6 9 2 15 18 21 24 21 30 0 3 6 9 12 5 18 21 21 30 ·me, (month) EMD ime (mol’l1!h} Number at ris!k - Nu.mber a.t l’lsk ! : I Non 15 15 13 11 11 10 8 •6 .2 2 0 23 20 17 17 15 13 8 3 ED ~ !;Alll 2~ • and Non- II D 9 8 1 6 6 5 5 2 2 ‘ ‘ ‘ ‘ ‘ ‘ ‘ ‘ ‘ ‘ g, ‘ ‘ ‘ ‘ ‘ ‘ 0 J 6 9 12 15 18 2 1 24 27 30 0 J •6 12 15 18 21 24 27 J8 Time (monlh) EMD T“me ( om J All rrMM Patients rrMM Patients with EMD No. of subjects 24 15 Median follow-up 30.1 months Median PFS 23.1 months 23.1 months 1-year PFS 74.4% 73.3% ✓ Median PFS for EMD patients was 23.1 months vs. Carvykti’s 13.8 months 1Li, J., et. al. “REDEEM-1, A MULTICENTER OPEN-LABEL PHASE 1/2A STUDY OF A BCMA/CD19 DUAL-TARGETING CAR-T THERAPY IN PATIENTS WITH RELAPSED/REFRACTORY MULTIPLE ~TEMPEST 14 MYELOMA INCLUDING THOSE WITH EXTRAMEDULLARY DISEASE”. Cytotherapy 28 (2026) 1268., Interim data update, May 6, 2026. ~ THERAPEUT I CS


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TPST-2003 Dual CAR-T for rrMM1: Safety Profile TEAEs1 TEAEs TRAEs TRAEs N=20 CRS2 (n,%) ICANS (n,%) N=20 (n,%) Gr~ 3 (n,%) (n,%) Gr~ 3 (n,%) Grade 1-2 17 (85.0) 3 (15.0) Hematologic (TEAEs ~ 5% All Grades) Grade 3 1 (5.0) 2 (10.0) Leukopenia 17(85.0) 14(70.0) 16(80.0) 12(60.0) Thrombocytopenia 17(85.0) 8(40.0) 16(80.0) 6(30.0) Grade 4-5 0 (0) 0 (0) Anemia 16(80.0) 8(40.0) 15(75.0) 6(30.0) All Grade 18 (90.0) 5 (25.0) Neutropenia 16(80.0) 10(50.0) 15(75.0) 9(45.0) Lymphopenia 16(80.0) 16(80.0) 14(70.0) 11 (55.0) Non-Hematologic (TEAEs ~ 5% All Grades) CRS any grade Median (days) Min, Max (days) LOH increase 16(80.0) 0 7(35.0) 0 Time to onset 4 1, 9 Hyperferritinaemia 15(75.0) 0 14(70.0) 0 Elevated D-dimer 13(65.0) 0 13(65.0) 0 Duration 4 2, 15 Hypoalbuminemia 11 (55.0) 0 0 0 Urinary tract infection 8(40.0) 2(10.0) 2(10.0) 0 MT increase 8(40.0) 0 8(40.0) 0 ICANS any grade Median (days) Min, Max (days) Hypogam maglobuli naemia 12(60.0) 0 12(60.0) 0 Diarrhoea 7(35.0) 0 2(10.0) Time to onset 10 8, 23 0 FOP increase 8(40.0) 0 8(40.0) 0 Duration 3 1,9 AST increase 8(40.0) 0 8(40.0) 0 Pneumonia 8(40.0) 6(30.0) 5(25.0) 4(20.0) □ All CRS and ICANS were manageable and resolved by SOC Prolonged PT 6(30.0) 0 6(30.0) 0 ( Tocilizumab, vasopressors and dexamethasone) Hypokalemia 4(20.0) 3(15.0) 3(15.0) 1(5.0) □ Totally 4 deaths occurred , including 2 for therapy-related Upper respiratory infection 4(20.0) 1(5.0) 0 0 pneumonia on 062 and 0103, and 2 deaths for PD Hypofibrinogenemia 4(20.0) 0 4(20.0) 0 1AE were graded according to CTCAE v5.0, 2CRS criteria (ASBMT consensus grading); FOP: Fibrin degradation products, ALT: Alanine aminotransferase, AST: Aspartate aminotransferase, LOH: lactate dehydrogenase; PT: Prothrombin time; CRS: Cytokine release syndrome, ICANS: !EC-associated neurotoxicity Syndrome, PD: Disease progression 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory ~TEMPEST 15 Multiple Myeloma Including Those with Extramedullary Disease”. Blood 144 (2024) 923-924. ~ THERAPEUT I CS


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TPST-2003 Dual CAR-T for rrMM1: Expansion and Persistence CAR-T cell positivity rate-time plot-BCMA+ (PKPS) CAR-T cell VCN-time plot (PKPS) 270000 90 <( 250000 ~ 230000 80 Cl 210000 :::1. ~ ~ 70 ui 190000 u QI 00 60 ‘ii 170000 2 8 150000 ~ so ~ ai 130000 1 40 ‘iii i 110000 \ 0 a. 30 ~ 90000 \ ai >, 70000 \ \ ~ “ 20 C. 0 50000 \ u ,_ t3 10 0 30000 .... u 10000 QI > -10000 -10 ..,.__—————-~———-~ -30000 Lymphod DO DI D3 DS D7 DIO Dl4 D21 D28 M2 M3 M6 M9 MIS M21 M24 Lymphod DO D1 D3 DS D7 D10 D14 D21 D28 M2 M3 M6 M9 M15 M21 M24 epletion Visit time epletion Visit time I-+- l .01ClOlq: -0 · 2.0~lOJ’itJ -+- ‘.lll~ l lllq I 1 —- l.Q IC 1O/k,g -e. 2.0 IC 101kg -+- 3.0 IC 10,‘kg I CAR-T cell positivity rate-time plot-CD19+ (PKPS) CAR-T cell VCN PK DL1 DL2 DL3 35 parameter (PKPS) (N=3) (N=10) (N=7) a, 30 8 25 Median T max(D) 14 11 .50 9 d, ! 20 ·;; Median Cmax(copies/µg) 97014.00 168218.00 83878.00 ~ 15 8_ ] 10 Median AUC _ lD ·copies/µg) 716037.01 1430939.38 437946.63 1-;- 0 Cl:’. u <I: 5 Median AUCo-int(D ·copies/µg) 1168278.89 1705951.87 509249 .27 -5 Among pts with 6 and 12 mo’ follow-up, 66.7% (10/15) and 50 .0% (4/8) had ..,.__———-+———-~~~-~-~~ Lymphod DO DI D3 DS D7 DIO Dl4 D21 D28 M2 M3 M6 M9 MIS M21 M24 epletion Visit time detectable CAR+T cells above the level of quantification (2 cells/µL) in PB. I-+- l .0 ~10/ki -e—2.0• IO~ -+- :SD ~lO~ I 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory ~TEMPEST 16 Multiple Myeloma Including Those with Extramedullary Disease”. Blood 144 (2024) 923-924. ~ THERAPEUT I CS


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TPST-2003 Dual CAR-T for rrMM: Conclusions TPST-20031,2 is the world’s first parallel-structure dual-target CAR-T cell therapy for rrMM with EMD & POEMS syndrome • REDEEM-1 Phase 1/2a (rrMM) and POEMS-1 Phase 1 (POEMS syndrome) • 44 patient target – 32 in REDEEM-1 and 12 in POEMS-1 • 20 patients dosed as of May 6, 2026 – 13 in REDEEM-1, 7 in POEMS-1 • 100% CR rate among CAR-T-naïve patients (15/15) – REDEEM-1 (10/10 CR) and POEMS-1 (5/5 CRVEGF) efficacy-evaluable as of March 31, 2026 and January 31, 2026, respectively • No grade ≥3 CRS, no grade ≥3 ICANS in REDEEM-1, Phase 1 enrollment complete (12/12), Phase 2a currently enrolling, first patient dosed May 2, 2026 • Phase 1/2 Investigator-Initiated Trial (rrMM) – Enrollment complete (24 patients) • 100% ORR among all 19 patients with measurable disease at baseline, 89.5% CR rate (17/19), 100% CR rate at highest dose level (5/5) • Median PFS of 23.1 months across all patients (24/24), median PFS of 23.1 months in EMD patients (15/15) • All evaluable patients at month 12 were MRD-negative (5/5) 1Jiang, H., et. al. “A Prospective Investigator-Initiated Phase 1/2 Study of BCMA/CD19 Dual-Targeting CAR T Therapy in Patients with Relapsed/Refractory Multiple Myeloma Including Those with ~TEMPEST Extramedullary Disease”. Blood 144 (2024) 923-924., 2Li, J., et. al. “REDEEM-1, A MULTICENTER OPEN-LABEL PHASE 1/2A STUDY OF A BCMA/CD19 DUAL-TARGETING CAR-T THERAPY IN 17 THERAPEUT I CS PATIENTS WITH RELAPSED/REFRACTORY MULTIPLE MYELOMA INCLUDING THOSE WITH EXTRAMEDULLARY DISEASE”. Cytotherapy 28 (2026) 1268., Interim data update, May 6, 2026.


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TPST-2003 Shows Similar Favorable Safety Profile to Approved BCMA CAR-T TPST-20031 Abecma Carvykti (BMS)2 (J&J/Legend)3 Target CD19, BCMA BCMA BCMA Stage REDEEM-1 Phase 1/2a Approval Approval Indication rrMM rrMM rrMM Target Dose 1x106 cells/kg 2x106 cells/kg 3x106 cells/kg 420x106 cells 0.75x106 cells/kg CRS% (N) 66.7% (2) 100% (3) 100% (6) 85% 84% CRS% Gr≥3 (N) 0% 0% 0% 9.3% 4% ICANS% (N) 0% 0% 16.7% (1) 28% 13% ICANS% Gr ≥3 (N) 0% 0% 0% 4% 2% CRS and ICANS were manageable and reversible, showing a favorable safety profile comparable to existing therapies 1Li, J., et. al. “REDEEM-1, A MULTICENTER OPEN-LABEL PHASE 1/2A STUDY OF A BCMA/CD19 DUAL-TARGETING CAR-T THERAPY IN PATIENTS WITH RELAPSED/REFRACTORY MULTIPLE MYELOMA INCLUDING THOSE WITH EXTRAMEDULLARY DISEASE”. Cytotherapy 28 (2026) 1268., Interim data update, May 6, 2026. 2. Abecma TM label at https://www.abecmahcp.com/safety/crs, accessed Nov 2025. 3. Carvykti TM label at ~TEMPEST 18


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TPST-2003 Performance Relative to Approved Therapies TPST-20031 Abecma Carvykti (BMS)2 (J&J/Legend)3 Target CD19, BCMA BCMA BCMA Stage Phase 1/2 IIT Approval Approval Indication rrMM rrMM rrMM KarMMa CARTITUDE-1 Trial IIT (NCT 03361748) (NCT 03548207) Number of 15 50 19 EMD patients Median PFS of EMD patients 23.1 months 7.9 months 13.8 months “Patients… with EMD demonstrate significantly inferior Day 90 ORR [following treatment with Abecma ] and presence of EMD is an independent risk factor for inferior PFS.” - Saurabh Zanwar et al., ASCO 2024 Annual Meeting 1Li, J., et. al. “REDEEM-1, A MULTICENTER OPEN-LABEL PHASE 1/2A STUDY OF A BCMA/CD19 DUAL-TARGETING CAR-T THERAPY IN PATIENTS WITH RELAPSED/REFRACTORY MULTIPLE MYELOMA INCLUDING THOSE WITH EXTRAMEDULLARY DISEASE”. Cytotherapy 28 (2026) 1268., Interim data update, May 6, 2026. 2. Zanwar S, Sidana S, Shune L, et al. Impact of extramedullary multiple myeloma on outcomes with idecabtagene vicleucel.J Hematol Oncol. 2024;17(1):42. 3. Sidana, S. 2025 ASCO Annual Meeting. https://www.asco.org/abstracts-presentations/ABSTRACT496242, accessed November 2025. Certain data in this presentation are based on a 19 cross-trial comparison and are not based on head-to-head clinical trials. Cross trial comparisons are inherently limited and may suggest misleading similarities or differences in outcomes. Results of head-to-head comparisons may differ significantly from those set forth herein.


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Small Molecule Programs Amezalpat (TPST-1120) First-in-Class PPAR�� Antagonist TPST-1495 First-in-Class Dual EP2/4 Antagonist


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® Developing Advanced Therapies for Cancer Patients May 6, 2026

FAQ

What did Tempest Therapeutics (TPST) report about TPST-2003 efficacy?

Tempest reported that TPST-2003 achieved a 100% complete response rate in 15 CAR-T-naïve efficacy-evaluable patients. This included 10 of 10 relapsed/refractory multiple myeloma patients in REDEEM-1 and 5 of 5 POEMS syndrome patients in POEMS-1 using standard response criteria.

How many patients have been treated with TPST-2003 so far?

Across all studies, 44 patients have received a single infusion of TPST-2003. This includes 24 patients in a prior Phase 1/2 investigator-initiated trial, 13 in the ongoing REDEEM-1 trial, and 7 in the ongoing POEMS-1 trial, forming one of the larger CD19/BCMA dual CAR-T datasets.

What progression-free survival was observed with TPST-2003 in multiple myeloma?

Median progression-free survival was 23.1 months across 24 relapsed/refractory multiple myeloma patients in the investigator-initiated trial. The same 23.1‑month median was reported for 15 patients with extramedullary disease, suggesting durable disease control in this difficult-to-treat subgroup.

What safety profile has TPST-2003 shown in the REDEEM-1 trial?

In REDEEM-1, Tempest reports no grade ≥3 cytokine release syndrome or ICANS among treated patients. Cytokine release syndrome and neurotoxicity events were described as manageable and reversible with standard-of-care measures, supporting a favorable early safety profile relative to existing BCMA CAR-T therapies.

Were there any deaths reported in TPST-2003 clinical studies?

Yes. In the investigator-initiated trial, four deaths occurred: two due to therapy-related pneumonia and two attributed to disease progression. These events highlight that, despite strong responses, serious adverse outcomes and progression can still occur in this heavily pretreated patient population.

What are Tempest Therapeutics’ next steps for TPST-2003 development?

Tempest states that the observed responses and safety profile support its objective of meeting with the U.S. Food and Drug Administration to discuss initiating a U.S. registrational study of TPST-2003 later in 2026. Ongoing Phase 2a enrollment in REDEEM-1 is also continuing.

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