MacroGenics (MGNX) advances MGC026 Phase 1 solid tumor trial with ESMO data
Rhea-AI Filing Summary
MacroGenics, Inc. reported an update on its ongoing Phase 1 study of MGC026, a B7-H3–directed antibody-drug conjugate for advanced solid tumors. Dose escalation from 1 mg/kg to 9 mg/kg q3W has been completed, and a 7.5 mg/kg q3W dose is being evaluated in four tumor-specific cohorts, including squamous cell carcinoma of the head and neck (SCCHN), endometrial cancer, melanoma and soft tissue sarcoma.
The SCCHN cohort, designed under Simon’s two-stage design with a planned 40-patient enrollment, has met the pre-specified Stage 1 response threshold and is now enrolling Stage 2. As of July 8, 2026, 74 patients had been enrolled across dose escalation and cohort expansion. No cases of interstitial lung disease or ocular toxicity had been reported, and evidence of anti-tumor activity was observed in several indications. MacroGenics plans to present dose-escalation and preliminary cohort data at the ESMO 2026 Congress in Madrid, including a poster on MGC026 on October 23, 2026 and a separate poster on lorigerlimab in advanced gynecologic cancers on October 26, 2026.
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8-K Event Classification
2 items: 8.01, 9.01
2 items
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.
Key Figures
Dose escalation range: 1 mg/kg to 9 mg/kg q3W
Selected cohort dose: 7.5 mg/kg q3W
SCCHN planned enrollment: 40 patients
+4 more
7 metrics
Dose escalation range
1 mg/kg to 9 mg/kg q3W
MGC026 doses evaluated in the Phase 1 dose-escalation portion
Selected cohort dose
7.5 mg/kg q3W
Dose being evaluated in four tumor-specific expansion cohorts
SCCHN planned enrollment
40 patients
Target enrollment for the SCCHN cohort under Simon’s two-stage design
Total patients enrolled
74 patients
Enrolled as of July 8, 2026 across dose escalation and cohort expansion
ESMO MGC026 presentation number
1020P
Poster presentation identifier for the MGC026 Phase 1 study at ESMO 2026
ESMO lorigerlimab presentation number
1278P
Poster presentation identifier for the LINNET Phase 2 lorigerlimab study
Drug-to-antibody ratio
4
MGC026 DAR for the SYNtecan E topoisomerase I inhibitor-based payload
Key Terms
Simon’s two-stage design, antibody-drug conjugate (ADC), B7-H3, interstitial lung disease, +2 more
6 terms
Simon’s two-stage design medical
"SCCHN cohort employs a Simon’s two-stage design, with a planned enrollment"
antibody-drug conjugate (ADC) medical
"MGC026, a novel B7-H3-directed antibody-drug conjugate (ADC), incorporating"
An antibody-drug conjugate (ADC) is a targeted medical treatment that combines an antibody, which acts like a guided missile seeking out specific cells, with a powerful drug to destroy those cells. It is designed to deliver medication directly to diseased cells, minimizing damage to healthy tissue. For investors, ADCs represent innovative therapies with potential for high growth, especially if they prove effective in treating difficult-to-cure conditions.
B7-H3 medical
"MGC026 is an investigational antibody-drug conjugate (ADC) targeting B7-H3, a protein"
B7‑H3 (CD276) is a protein that sits on the surface of certain cells, including many cancer cells, and can help tumors hide from the immune system—like a disguise that makes them harder for the body's defenses to spot. Investors watch B7‑H3 because medicines designed to block or use this protein aim to reveal tumors or deliver targeted therapy; progress in trials, regulatory clearances, or deals around B7‑H3 programs can materially change a biotech company's prospects and valuation.
interstitial lung disease medical
"As of this date, there were no cases of interstitial lung disease or ocular toxicity"
A group of lung conditions that cause inflammation and scarring of the thin tissue between the air sacs, which makes it harder for oxygen to pass into the blood; imagine the lungs’ fine filters becoming stiff and less effective. Investors care because reports of interstitial lung disease can affect a drug’s safety profile, trigger regulatory warnings or label changes, and shift demand for treatments or create liability risks that influence a company’s valuation.
pharmacokinetics medical
"evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary"
Pharmacokinetics is the study of how a substance, such as a drug or chemical, moves through and is processed by the body over time. It tracks how it is absorbed, distributed, broken down, and eventually eliminated. For investors, understanding pharmacokinetics helps gauge the effectiveness, safety, and potential risks of new medications or treatments, which can influence a company’s success and valuation in the healthcare industry.
bispecific DART® molecule medical
"lorigerlimab, an investigational, bispecific DART® molecule that targets PD-1 and CTLA-4"
AI-generated analysis. How Rhea-AI works. Not financial advice.
FAQ
What clinical update did MacroGenics (MGNX) provide on MGC026?
MacroGenics reported interim Phase 1 results for MGC026, its B7-H3–targeted ADC in advanced solid tumors. Dose escalation is complete, four tumor-specific cohorts are ongoing, and the SCCHN cohort met the Stage 1 response threshold, triggering enrollment into Stage 2.
How many patients are in MacroGenics (MGNX) MGC026 Phase 1 trial and at what dose?
As of July 8, 2026, 74 patients had been enrolled in the MGC026 Phase 1 trial. Dose escalation from 1–9 mg/kg q3W is complete, and a 7.5 mg/kg q3W dose is being tested in four tumor-specific expansion cohorts.
What safety findings were reported for MGC026 by MacroGenics (MGNX)?
MacroGenics reported that, as of July 8, 2026, there were no cases of interstitial lung disease or ocular toxicity in the MGC026 Phase 1 trial. The company also noted evidence of anti-tumor activity across several solid tumor indications in the ongoing study.
When and where will MacroGenics (MGNX) present MGC026 data at ESMO 2026?
MacroGenics plans to present MGC026 Phase 1 data as a poster at the ESMO 2026 Congress in Madrid. The MGC026 poster (Presentation 1020P) is scheduled for October 23, 2026, from 15:15–16:00 CEST in the advanced solid tumors track.
What is the design of the SCCHN cohort in the MGC026 trial for MacroGenics (MGNX)?
The SCCHN cohort uses Simon’s two-stage design with a planned enrollment of 40 patients. MacroGenics has already achieved the pre-specified Stage 1 response threshold and is now enrolling patients into Stage 2 at the selected 7.5 mg/kg q3W dose.
What additional MacroGenics (MGNX) program will be presented at ESMO 2026?
MacroGenics will also present a poster on lorigerlimab, a bispecific DART molecule targeting PD-1 and CTLA-4, in advanced gynecologic cancers. The LINNET Phase 2 study poster (Presentation 1278P) is scheduled for October 26, 2026, from 12:00–12:45 CEST.
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): July 23, 2026
(Exact Name of Registrant as Specified in Charter)
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| (Address of Principal Executive Offices) | (Zip Code) | ||||||||||||||||
Registrant's telephone number, including area code: (301 ) 251-5172
Not applicable
(Former Name or Former Address, if Changed Since Last Report)
Securities registered pursuant to Section 12(b) of the Act:
| Title of each class | Trading Symbol(s) | Name of each exchange on which registered | ||||||
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 (see General Instruction A.2. below):
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 8.01 | Other Events. | ||||||||||||||||
On July 23, 2026, MacroGenics, Inc. issued a press release providing a clinical update on its ongoing Phase 1 study of MGC026.
A copy of the press release is attached to this Current Report on Form 8-K as Exhibit 99.1 and is incorporated by reference into this Item 8.01.
| Item 9.01 | Financial Statements and Exhibits | ||||||||||||||||
(d) Exhibits. | |||||||||||||||||
| Exhibit Number | Description of Exhibit | ||||||||||||||||
99.1 | Press Release dated July 23, 2026 | ||||||||||||||||
| 104 | Cover Page Interactive Data (embedded within the Inline XBRL document) | ||||||||||||||||
SIGNATURE
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.
Date: July 23, 2026 | MACROGENICS, INC. | |||||||||||||||||||||||||
By: /s/ Jeffrey Peters Name: Jeffrey Peters Title: Senior Vice President, General Counsel and Corporate Secretary | ||||||||||||||||||||||||||
Exhibit 99.1
MacroGenics Provides Clinical Update on Ongoing Phase 1 Study for MGC026
•Interim Phase 1 results accepted for poster presentation at ESMO Congress 2026
•Achieved pre-specified Stage 1 response threshold in squamous cell carcinoma of the head and neck (SCCHN) cohort and enrolling Stage 2 per Simon’s two-stage design
•Ongoing enrollment in other tumor-specific cohorts, including endometrial cancer, melanoma and soft tissue sarcoma
ROCKVILLE, Md., July 23, 2026 — MacroGenics, Inc. (NASDAQ: MGNX), a clinical-stage biopharmaceutical company focused on developing innovative antibody-based therapeutics for the treatment of cancer, today provided an update on the ongoing Phase 1 study evaluating MGC026, a novel B7-H3-directed antibody-drug conjugate (ADC), incorporating a topoisomerase I inhibitor-based linker-payload, in patients with advanced solid tumors. MacroGenics plans to present dose escalation and preliminary tumor-specific cohort results at the European Society for Medical Oncology (ESMO) 2026 Congress, taking place October 23-27, 2026, in Madrid, Spain.
The dose escalation portion of the study evaluated MGC026 at doses ranging from 1 mg/kg to 9 mg/kg administered every three weeks (q3W) and was completed in the fourth quarter of 2025. A dose of 7.5 mg/kg q3W is being further evaluated in four tumor-specific cohorts: recurrent or metastatic SCCHN, endometrial cancer, melanoma, and soft tissue sarcoma. The study is active at clinical sites in the United States, Australia and the United Kingdom.
The SCCHN cohort employs a Simon’s two-stage design, with a planned enrollment target of 40 patients. MacroGenics is currently enrolling SCCHN patients in Stage 2 after meeting the pre-specified response threshold in Stage 1. Enrollment in the other three cohorts continues as planned. As of July 8, 2026, a total of 74 patients had been enrolled across the dose escalation and ongoing cohort expansion portions of the study. As of this date, there were no cases of interstitial lung disease or ocular toxicity reported, and evidence of anti-tumor activity was observed across several indications.
“We look forward to sharing the data at ESMO and believe this presentation represents an important opportunity to demonstrate the potential of MGC026 as we continue its clinical development,” said Eric Risser, President and Chief Executive Officer of MacroGenics.
ESMO 2026 Poster Presentations
•Title: Phase 1, first-in-human study of MGC026, a B7-H3–targeted antibody-drug conjugate (ADC) in advanced solid tumors
Exhibit 99.1
•Presentation Number: 1020P
•Lead Author: Rachel E. Sanborn, M.D.
•Date: Friday, October 23, 2026
•Time: 15:15 – 16:00 CEST
The Company also plans to present the following poster on lorigerlimab, an investigational, bispecific DART® molecule that targets PD-1 and CTLA-4:
•Title: LINNET: A phase 2 study to evaluate lorigerlimab in participants (pts) with advanced gynecologic cancers
•Presentation Number: 1278P
•Lead Author: Amir Jazaeri, M.D.
•Date: Monday, October 26, 2026
•Time: 12:00 – 12:45 CEST
About MGC026
MGC026 is an investigational antibody-drug conjugate (ADC) targeting B7-H3, a protein with expression across the tumor microenvironment, including on tumor cells, tumor-associated stroma, and tumor-associated vasculature. MGC026 incorporates Synaffix’s proprietary ADC technology and the SYNtecan E™ topoisomerase I inhibitor-based linker-payload, which consists of a cleavable, exatecan-based cytotoxic payload conjugated at a drug-to-antibody ratio (DAR) of 4. MGC026 is designed to deliver this potent payload selectively to B7-H3-expressing tumors and is being developed for patients with advanced solid tumors. The ongoing Phase 1 study of MGC026 is an open-label clinical trial evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of MGC026 in patients with advanced solid tumors. Additional information about the study is available at www.clinicaltrials.gov using the identifier NCT0624270.
About MacroGenics, Inc.
MacroGenics (the Company) is a biopharmaceutical company focused on developing innovative monoclonal antibody-based therapeutics for the treatment of cancer. The Company generates its pipeline of product candidates primarily from its proprietary suite of next-generation antibody-based technology platforms, which have applicability across broad therapeutic domains. The combination of MacroGenics’ technology platforms and protein engineering expertise has allowed the Company to generate promising product candidates and enter into several strategic collaborations with global pharmaceutical and biotechnology companies. For more information, please see the Company’s website at www.macrogenics.com. MacroGenics, the MacroGenics logo and DART are trademarks or registered trademarks of MacroGenics, Inc.
Exhibit 99.1
Cautionary Note on Forward-Looking Statements
Any statements in this press release about future expectations, plans and prospects for MacroGenics (“Company”), including statements about the Company’s strategy, future operations, clinical development of and regulatory plans for the Company’s therapeutic candidates, expected timing of the release of clinical updates and safety and efficacy data for the Company’s ongoing clinical trials, anticipated cash runway and other statements containing the words “subject to”, "believe", “anticipate”, “plan”, “expect”, “intend”, “estimate”, “potential,” “project”, “may”, “will”, “should”, “would”, “could”, “can”, the negatives thereof, variations thereon and similar expressions, or by discussions of strategy, including our ability to execute on our key strategic priorities for 2026, constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: risks related to the reproducibility of any results initially seen in the interim MGC026 clinical data reported herein; risks that TZIELD, lorigerlimab, ZYNYZ, MGC026 or any other product or product candidate’s revenue, expenses and costs may not be as expected; risks relating to TZIELD, lorigerlimab, ZYNYZ, MGC026 or any other product candidate’s market acceptance, competition, reimbursement and regulatory actions; future data updates, including timing and results of efficacy and safety data with respect to product candidates in ongoing clinical trials; the uncertainties inherent in the initiation and enrollment of future clinical trials; the availability of financing to fund the internal development of our product candidates; expectations of expanding ongoing clinical trials; expectations for the timing and steps required in the regulatory review process; expectations for regulatory approvals; expectations of future milestone payments; the impact of competitive products; our ability to enter into agreements with strategic partners and other matters that could affect the availability or commercial potential of the Company's product candidates; business, economic or political disruptions due to catastrophes or other events, including natural disasters, terrorist attacks, civil unrest and actual or threatened armed conflict, or public health crises; costs of litigation and the failure to successfully defend lawsuits and other claims against us;; risks related to the transition of the CDMO operations to the purchaser in the Transaction, including the diversion of management's attention from the Company's ongoing business operations; risks related to the Company's post-closing manufacturing arrangements with Bora the purchaser in the Transaction, including under the manufacturing and supply agreement and the transition services agreement; the possibility that the anticipated benefits of the sale of the Company’s CDMO operations (the “Transaction”), including that the additional post-closing cash payments may not be earned or received, in whole or in part; the costs and expenses associated with the Transaction; potential litigation relating to the Transaction; and other risks described in the Company's filings with the Securities and Exchange Commission. In addition, the forward-looking statements included in this press release represent the Company's views only as of the date hereof. The Company anticipates that subsequent events and developments will cause the Company's views to change. However, while the Company may elect to update these forward-looking statements at some point in the future, the Company specifically disclaims any obligation to do so, except as
Exhibit 99.1
may be required by law. These forward-looking statements should not be relied upon as representing the Company's views as of any date subsequent to the date hereof.
CONTACTS
Jim Karrels, Senior Vice President, CFO
1-301-251-5172
info@macrogenics.com
Argot Partners
1-212-600-1902
macrogenics@argotpartners.com