Immatics ESMO Data: IMA402 32% cORR in PRAME-High Melanoma, IMA203CD8 55% cORR in Gynecologic Cancers
IMTX is trading near its 52-week low of $6.65 (9.9% above the low).
Summary
Immatics released full ESMO 2026 data: IMA402 posted a 32% confirmed response rate in PRAME-high melanoma with 91% one-year survival, while IMA203CD8 showed a 55% confirmed response rate in gynecologic cancers at clinically relevant doses. Both are early-stage cohorts, and the Phase 3 SUPRAME readout is the next real test.
Key Events · Product Development and Regulatory · IMTX
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IMA402 Hits 32% cORR in PRAME-High Melanoma
In 22 PRAME-high melanoma patients, all previously treated with checkpoint inhibitors, IMA402 produced a 32% confirmed objective response rate (7/22) and 32% across all PRAME-high indications (10/31).
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Durability and Survival Support IMA402
Median duration of response was 12.5 months (median follow-up 16.8 months) and median overall survival was not reached, with 91% of patients alive at one year versus 60% treated below the recommended Phase 2 dose range.
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IMA203CD8 Shows 55% cORR in Gynecologic Cancers
At clinically relevant doses (>=DL4c) in 20 ovarian and uterine cancer patients, IMA203CD8 delivered 60% ORR and 55% cORR (11/20), with median duration of response 8.4 months and median progression-free survival 5.8 months.
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Broad Activity Across PRAME-Positive Tumors
Across all dose levels and 90 evaluable patients, IMA203CD8 showed 51% ORR (46/90) and 41% cORR (36/87), including 67% cORR (8/12) in synovial sarcoma and ongoing responses beyond 2.5 years.
Analysis · IMTX · Life Sciences
The full ESMO 2026 dataset behind the 2026-10-24 headline is out, and the piece the market has not yet seen is IMA203CD8: a 55% confirmed response rate in 20 heavily pretreated gynecologic cancer patients at clinically relevant doses, with responses also in synovial sarcoma and melanoma. That broadens the PRAME franchise from a single melanoma bet into a tumor-agnostic story, which is what the pipeline is valued on. For IMA402, the melanoma numbers (32% cORR, 12.5-month median duration, 91% alive at one year) are competitive for an off-the-shelf bispecific in post-checkpoint patients, and the safety profile stayed clean with no ICANS and no drug-related Grade 5 events. The offset: these are small, early cohorts with a June 1, 2026 cutoff, and the real value test remains the Phase 3 SUPRAME topline for anzu-cel, guided to 1H 2027.
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At the time of this filing, IMTX was trading at $7.31 on NASDAQ in the Life Sciences sector, with a market capitalization of approximately $1.1B. The 52-week trading range was $6.65 to $12.41. This filing was assessed with positive market sentiment and an importance score of 7 out of 10.