Kazia Therapeutics Reports Encouraging Preliminary Clinical Responses in Ongoing Phase 1b Study of Paxalisib in Late-Stage Metastatic Triple-Negative Breast Cancer

Rhea-AI Summary

Kazia Therapeutics (NASDAQ: KZIA) reported preliminary clinical responses from its ongoing Phase 1b study of paxalisib combined with pembrolizumab and chemotherapy in late-stage metastatic triple-negative breast cancer (TNBC). To date, three patients treated with paxalisib-based regimens showed meaningful responses: two partial responses in trial participants and one confirmed complete metabolic response under expanded access. Median time on treatment is ~6.1 months, all patients remain on therapy, and paxalisib at 30 mg daily showed generally favorable tolerability. The company plans additional site activations and targets 12 TNBC patients by end-2026 with topline data in early 2027.

Positive

• Two of two evaluable Phase 1b patients achieved partial responses
• One confirmed complete metabolic response observed under expanded access
• Median time on treatment approximately 6.1 months
• Paxalisib tolerable at 30 mg daily with mostly mild-to-moderate AEs
• Planned activation of four additional sites in 2026 and enrollment target of 12 TNBC patients by end-2026

Negative

• Clinical update reports outcomes from only three patients (very small sample)
• Two serious adverse events reported to date (both deemed unrelated to paxalisib)
• Pembrolizumab cohort limited to PD-L1–positive disease (CPS ≥10), narrowing applicability

News Market Reaction

-9.84%

20 alerts

-9.84% News Effect

-33.3% Trough in 2 hr 31 min

-$9M Valuation Impact

$85M Market Cap

1.4x Rel. Volume

On the day this news was published, KZIA declined 9.84%, reflecting a notable negative market reaction. Argus tracked a trough of -33.3% from its starting point during tracking. Our momentum scanner triggered 20 alerts that day, indicating elevated trading interest and price volatility. This price movement removed approximately $9M from the company's valuation, bringing the market cap to $85M at that time.

Data tracked by StockTitan Argus on the day of publication.

Key Figures

Patients with responses: 3 patients Partial responses: 2 of 2 evaluable patients Complete metabolic response: 1 patient +5 more

8 metrics

Patients with responses 3 patients Metastatic TNBC treated with paxalisib-based regimens

Partial responses 2 of 2 evaluable patients Phase 1b paxalisib + pembrolizumab + chemotherapy trial

Complete metabolic response 1 patient Expanded access paxalisib + pembrolizumab/chemotherapy

Median time on treatment 6.1 months Patients in ongoing Phase 1b study

Paxalisib dose 30 mg daily Combination with pembrolizumab and chemotherapy

AEs unrelated to paxalisib Approximately 75% Adverse events assessed as unlikely or unrelated to paxalisib

Serious adverse events 2 SAEs Both deemed unrelated to paxalisib

Planned TNBC enrollment 12 patients Targeted TNBC enrollment by end of 2026

Market Reality Check

Price: $6.56 Vol: Volume 358,774 is 40% abo...

normal vol

$6.56 Last Close

Volume Volume 358,774 is 40% above the 20-day average of 256,988, indicating elevated interest into this update. normal

Technical At $7.93, KZIA trades above its 200-day MA of $7.26 and sits 177.27% above its 52-week low but 54.43% below its 52-week high.

Peers on Argus

KZIA is up 5.59% while close peers are mostly negative (e.g., MBRX -3.19%, XTLB ...

KZIA is up 5.59% while close peers are mostly negative (e.g., MBRX -3.19%, XTLB -9.22%). LPTX shows an outsized move of +238.84%, but overall peer moves are mixed, pointing to a stock-specific reaction for KZIA.

Historical Context

5 past events · Latest: Jan 08 (Positive)

Pattern 5 events

Date	Event	Sentiment	Move	Catalyst
Jan 08	Conference participation	Positive	+1.5%	JPM conference participation and promise of near-term paxalisib clinical update.
Dec 22	Listing compliance	Positive	-8.0%	Regained full Nasdaq compliance supported by a $50M private placement.
Dec 10	Clinical data update	Positive	-17.8%	New paxalisib data showing tumor shrinkage and CTC reductions in breast cancer.
Dec 02	Private placement	Neutral	+9.9%	Pricing of $50M equity private placement to fund paxalisib and pipeline.
Nov 18	Clinical and business update	Neutral	-5.3%	Initial immune-complete response plus broader pipeline and Nasdaq MVLS update.

Pattern Detected

KZIA has previously seen weak or negative price reactions to positive clinical and regulatory updates, with only some financing and conference-related news trading in line with sentiment.

Recent Company History

Over recent months, KZIA has focused on strengthening its balance sheet and advancing paxalisib. A $50M private placement and subsequent filings extended cash runway and helped regain full Nasdaq compliance by Dec 18, 2025. Multiple paxalisib data updates, including an initial immune-complete response in metastatic TNBC and broader translational findings, were followed by mixed or negative price reactions. Today’s positive move on new Phase 1b responses contrasts with earlier selloffs on encouraging data.

Market Pulse Summary

The stock moved -9.8% in the session following this news. A negative reaction despite positive early...

Analysis

The stock moved -9.8% in the session following this news. A negative reaction despite positive early responses would have fit prior patterns where encouraging paxalisib data coincided with weak price performance. With partial and complete metabolic responses in late-stage TNBC and generally manageable safety at 30 mg, fundamental signals appear constructive, but past financing needs and listing issues have weighed on sentiment. Future data from the planned 12-patient TNBC cohort and broader breast cancer studies could further influence perception.

Key Terms

triple-negative breast cancer, pembrolizumab, olaparib, pd-l1, +4 more

8 terms

triple-negative breast cancer medical

"Phase 1b study evaluating paxalisib in... metastatic triple-negative breast cancer (TNBC)."

Triple-negative breast cancer is a type of breast cancer that lacks three common markers used to identify and treat the disease effectively. Because it doesn’t respond to some targeted therapies, it can be more difficult to treat and may have a more aggressive progression. This impacts the development of new treatments and can influence the outlook for healthcare companies involved in cancer research and pharmaceuticals.

pembrolizumab medical

"paxalisib-based regimens... in combination with pembrolizumab and chemotherapy"

A cancer immunotherapy drug that helps the body’s immune system recognize and attack tumor cells by blocking a molecular “brake” that tumors use to hide. Investors watch it because regulatory approvals, clinical trial results, dosing rules, and competition directly affect potential sales, profit forecasts, and the valuation of companies that sell or license the drug—think of trial outcomes as checkpoint signs that can open or close a revenue road.

olaparib medical

"in combination with either: Pembrolizumab plus chemotherapy... or Olaparib"

Olaparib is an approved cancer medicine that blocks a key repair pathway inside certain tumor cells, causing those cells to die while sparing most healthy tissue. Think of it like disabling the repair crew on damaged machinery so broken parts can’t be fixed. Investors track olaparib because regulatory approvals, clinical trial outcomes, patent life and pricing determine revenue potential and competitive position in oncology drug markets.

pd-l1 medical

"Eligibility... required PD-L1–positive disease (CPS ≥10)"

PD-L1 is a protein found on the surface of some cells that acts like a stop sign for the immune system, telling certain immune cells to back off. It matters to investors because many cancer drugs and diagnostic tests target or measure PD-L1 to unlock immune responses or predict which patients will benefit, affecting clinical success, regulatory approval, and potential sales in the oncology market.

fdg pet/ct medical

"On November 10, 2025, FDG PET/CT imaging demonstrated no evidence of active malignancy"

FDG PET/CT is a combined medical imaging test that injects a harmless sugar-like tracer (FDG) to map active cells and then overlays that map on a detailed body scan (CT). It shows where tissues are unusually active—often indicating tumors, inflammation, or treatment response—so investors can assess a drug or device’s effectiveness, diagnostic value, and potential market impact the way a heat map helps locate hotspots in a city.

hyperglycemia medical

"At the 30 mg daily dose, one case of Grade 1 hyperglycemia has been observed"

Hyperglycemia is a condition where there is too much sugar in the bloodstream because the body cannot move glucose into cells effectively, like a sink with the drain partially blocked so water pools. It matters to investors because persistent high blood sugar drives demand for diabetes treatments, medical devices and hospital care, affects clinical trial outcomes and regulatory decisions, and can signal long-term cost and liability risks for healthcare companies.

serious adverse events medical

"Two serious adverse events (SAEs) have been reported to date"

Serious adverse events are significant problems or negative outcomes that occur during a medical treatment or clinical trial, such as severe side effects, hospitalizations, or life-threatening conditions. They matter to investors because such events can impact a company's reputation, lead to regulatory scrutiny, or delay the development of new products, ultimately affecting the company’s financial performance.

expanded access program regulatory

"one confirmed complete metabolic response (CR) in a patient treated under an expanded access program."

A program that allows patients with serious or life‑threatening conditions to receive an experimental drug or therapy before it is fully approved by regulators, when they cannot join clinical trials. Investors care because expanded access can change a treatment’s market perception, create early real‑world safety or demand signals, and affect regulatory timelines and potential revenue — like a pre‑order system that also reveals how the product performs outside controlled testing.

AI-generated analysis. Not financial advice.

SYDNEY, Jan. 27, 2026 /PRNewswire/ -- Kazia Therapeutics (NASDAQ: KZIA), today provided a clinical update from its ongoing Phase 1b study evaluating paxalisib in combination with pembrolizumab and chemotherapy in patients with late-stage (Stage IV), metastatic triple-negative breast cancer (TNBC).

To date, three patients with metastatic TNBC treated with paxalisib-based regimens have demonstrated meaningful clinical responses, including two partial responses (PRs) in trial participants and one confirmed complete metabolic response (CR) in a patient treated under an expanded access program.

Clinical Highlights

• 2 of 2 evaluable patients enrolled in the Phase 1b trial achieved partial responses
• One advanced metastatic TNBC patient achieved a confirmed complete metabolic response following re-treatment with pembrolizumab/chemotherapy plus paxalisib (under an expanded access protocol)
• Responses observed in patients with visceral disease and multi-organ metastases
• Median time on treatment to date is approximately 6.1 months, with all patients continuing on therapy at the time of this update
• Paxalisib continues to demonstrate a generally favorable safety and tolerability profile when combined with pembrolizumab and chemotherapy at the 30 mg daily dose

The ongoing Phase 1b trial is a multi-center, open-label, randomized study initiated in June 2025 designed to evaluate the safety, tolerability, and preliminary clinical activity of paxalisib in patients with advanced breast cancer, including TNBC, in combination with either: Pembrolizumab plus chemotherapy (current standard-of-care first-line regimen) or Olaparib (advanced breast cancer patients with BRCA mutations). Eligibility for the pembrolizumab-containing cohort required PD-L1–positive disease (CPS ≥10), consistent with standard-of-care practice in metastatic TNBC.

Patient 1 – Partial Response
A 61-year-old female with metastatic TNBC involving the left upper lobe of the lung, initiated treatment with paxalisib (30 mg daily) in combination with pembrolizumab and gemcitabine/carboplatin in June 2025. After nine cycles of therapy, serial imaging demonstrated continued tumor reduction at each assessment, culminating in a partial response by iRECIST criteria. The patient remains active on study.

Patient 2 – Partial Response with Complete Resolution of a Target Lesion
A 47-year-old female with extensively metastatic TNBC involving the lung, liver, bone, and lymph nodes, initiated treatment with paxalisib (30 mg daily) in combination with pembrolizumab and gemcitabine/carboplatin in October 2025. Following three treatment cycles, imaging demonstrated a partial response, including complete resolution of a target lung lesion and the patient remains active on study.

Patient 3 – Confirmed Complete Metabolic Response
A 44-year-old female with metastatic TNBC who had previously received pembrolizumab/chemotherapy experienced disease progression involving bone and lung metastases in early 2025. Although ineligible for the formal trial due to prior pembrolizumab exposure, the patient was re-treated beginning in June 2025 with pembrolizumab/chemotherapy plus paxalisib (30 mg daily) under physician supervision. On November 10, 2025, FDG PET/CT imaging demonstrated no evidence of active malignancy, consistent with a complete metabolic response. This complete metabolic response was confirmed on follow-up imaging in January 2026, and the patient remains on paxalisib and pembrolizumab therapy.

Paxalisib has been generally well tolerated in combination with pembrolizumab and chemotherapy. Approximately 75% of adverse events (AEs) were assessed as unlikely or unrelated to paxalisib. The paxalisib-related AEs were expected and predominantly mild to moderate, consistent with prior studies. At the 30 mg daily dose, one case of Grade 1 hyperglycemia has been observed, requiring no intervention. Two serious adverse events (SAEs) have been reported to date, both deemed unrelated to paxalisib.

Following an initial targeted site activation phase designed to ensure rigorous protocol execution and informed by encouraging early clinical signals from the first patients treated, the Company expects to activate two additional clinical sites by April 2026, with two further sites planned for mid-2026. Kazia continues to anticipate the targeted enrollment of twelve TNBC pts target by the end of 2026 and topline data readout in early 2027

Kazia is also evaluating paxalisib in additional breast cancer populations, including earlier-stage TNBC and hormone receptor–positive, HER2-negative (HR+ / HER2-) breast cancer, where dysregulation of the PI3K/mTOR pathway is well established. Paxalisib's oral, once-daily administration offers a potentially convenient treatment option with minimal incremental burden to patients and clinical sites, an important consideration as the Company explores expansion into broader breast cancer populations. The Company will provide updates as these programs advance.

"While these observations represent a preliminary read from ongoing studies, the consistency and depth of responses we are seeing including tumor regression across multiple metastatic sites and a complete metabolic response are highly encouraging," said Dr. John Friend, M.D., Chief Executive Officer of Kazia Therapeutics. "Confirmed complete responses in metastatic triple-negative breast cancer are exceedingly rare, particularly in patients who have already progressed on standard therapies. These early data reinforce our belief that paxalisib has the potential to meaningfully enhance the activity of existing immunotherapy-based regimens, and we look forward to generating additional clinical and translational insights throughout the year."

For investor and media, please contact Mike Moyer, Managing Director LifeSci Advisors LLC, mmoyer@lifesciadvisors, +1-617-308-4306.

About Kazia Therapeutics

Kazia Therapeutics Limited (NASDAQ: KZIA) is an oncology-focused drug development company, based in Sydney, Australia. Our lead program is paxalisib, an investigational brain penetrant inhibitor of the PI3K / Akt / mTOR pathway, which is being developed to treat multiple forms of cancer. Licensed from Genentech in late 2016, paxalisib is or has been the subject of ten clinical trials in this disease. A completed Phase 2/3 study in glioblastoma (GBM-Agile) was reported in 2024, and discussions are ongoing for designing and executing a pivotal registrational study in pursuit of a standard approval. Other clinical trials involving paxalisib are ongoing in advanced breast cancer, brain metastases, diffuse midline gliomas, and primary central nervous system lymphoma, with several of these trials having reported encouraging interim data. Paxalisib was granted Orphan Drug Designation for glioblastoma by the U.S. Food and Drug Administration (FDA) in February 2018, and Fast Track Designation (FTD) for glioblastoma by the FDA in August 2020. Paxalisib was also granted FTD in July 2023 for the treatment of solid tumor brain metastases harboring PI3K pathway mutations in combination with radiation therapy. In addition, paxalisib was granted Rare Pediatric Disease Designation and Orphan Drug Designation by the FDA for diffuse intrinsic pontine glioma in August 2020, and for atypical teratoid / rhabdoid tumors in June 2022 and July 2022, respectively. Kazia is also developing EVT801, a small molecule inhibitor of VEGFR3, which was licensed from Evotec SE in April 2021. Preclinical data has shown EVT801 to be active against a broad range of tumor types and has provided evidence of synergy with immuno-oncology agents. In addition to its clinical-stage programs, Kazia is advancing NDL2, a potentially first-in-class nuclear PD-L1 protein degrader program targeting a newly identified mechanism of immunotherapy resistance and metastatic progression, currently in preclinical development. For more information, please visit www.kaziatherapeutics.com or follow us on X @KaziaTx.

Forward-Looking Statements

This announcement may contain forward-looking statements, which can generally be identified as such by the use of words such as "may," "will," "estimate," "future," "forward," "anticipate," or other similar words. Any statement describing Kazia's future plans, strategies, intentions, expectations, objectives, goals or prospects, and other statements that are not historical facts, are also forward looking statements, including, but not limited to, the plan to activate additional clinical sites for the Phase 1b study in 2026, the anticipated completion of enrolment in the Phase 1b clinical trial in the fourth quarter of 2026, the anticipated topline data readout in early 2027, the potential of paxalisib's oral, once-daily administration to offer a convenient treatment option with minimal incremental burden to patients and clinical sites, the opportunities of evaluating paxalisib in additional breast cancer populations, and the potential benefits of paxalisib. Such statements are based on Kazia's current expectations and projections about future events and future trends affecting its business and are subject to certain risks and uncertainties that could cause actual results to differ materially from those anticipated in the forward-looking statements, including risks and uncertainties associated with clinical and preclinical trials and product development, including the risk that interim or early data may not be consistent with final data, risks related to regulatory approvals, risks related to the impact of global economic conditions, and risks related to Kazia's ability to regain and/or maintain compliance with the applicable Nasdaq continued listing requirements and standards. These and other risks and uncertainties are described more fully in Kazia's Annual Report, filed on form 20-F with the SEC, and in subsequent filings with the United States Securities and Exchange Commission. Kazia undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events, or otherwise, except as required under applicable law. You should not place undue reliance on these forward-looking statements, which apply only as of the date of this announcement.

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SOURCE Kazia Therapeutics Limited

FAQ

What clinical responses did Kazia report for paxalisib in TNBC (KZIA) on January 27, 2026?

Kazia reported two partial responses in trial patients and one confirmed complete metabolic response under expanded access.

How long have patients been on paxalisib treatment in Kazia's Phase 1b study (KZIA)?

Median time on treatment to date is approximately 6.1 months, and all reported patients remain on therapy.

What dose of paxalisib is being used in Kazia's Phase 1b TNBC study (KZIA) and is it tolerable?

Paxalisib is administered at 30 mg daily and was described as generally well tolerated with mostly mild-to-moderate adverse events.

When does Kazia expect topline data from the paxalisib TNBC cohort (KZIA)?

The company anticipates a topline data readout in early 2027.

How many TNBC patients does Kazia plan to enroll in the Phase 1b trial (KZIA) by end-2026?

Kazia targets enrollment of 12 TNBC patients by the end of 2026.