May 2026 Biotech Catalysts: 7 FDA Dates & Phase 3 Readouts

Phase 3 ATTAIN-1 topline data for orforglipron in obesity

Orforglipron · Obesity

First Phase 3 readout for Lilly's once-daily oral GLP-1, orforglipron. If it delivers meaningful weight loss without GI side effects worse than injectables, this becomes a $20B+ franchise and reshapes the obesity market overnight.

Phase 2 showed ~14.7% weight loss at 36 weeks. Phase 3 needs to confirm at 72 weeks while keeping discontinuation rates below 15%. Strong data sends LLY up 5-10%; weak data triggers competitive re-rating in Viking (VKTX), Structure (GPCR), and Terns (TERN).

Sponsor record: 94 of 1075 late-stage studies registered by Eli Lilly were stopped early. Trials stop for many reasons — see the company profile for each one.

Unverified — date is AI-generated and has not been checked against a primary source.

HARMONi-6 Phase 3 topline data for ivonescimab in 1L PD-L1+ NSCLC

Ivonescimab · First-line PD-L1+ non-small cell lung cancer

Summit's PD-1xVEGF bispecific antibody faces its definitive Phase 3 readout in the first-line lung cancer setting versus Keytruda. The 2024 HARMONi-2 study suggested ivonescimab could beat Keytruda in PD-L1+ patients. HARMONi-6 is the global confirmation.

Statistically significant PFS benefit over Keytruda would be a paradigm shift in immuno-oncology and put SMMT on a $30B+ revenue trajectory. A miss or wash sends the stock down 40-60% and resets the entire PD-1xVEGF bispecific thesis.

Unverified — date is AI-generated and has not been checked against a primary source.

Phase 3 CANOPY topline data for vosoritide in idiopathic short stature

Voxzogo (vosoritide) · Idiopathic short stature (ISS)

BioMarin tries to expand Voxzogo beyond achondroplasia into the much larger idiopathic short stature population. Approval would multiply the addressable market by 10x+ and rescue the franchise from disappointing achondroplasia uptake.

Primary endpoint is annualized growth velocity gain vs placebo. Phase 2 data was supportive. A successful readout could double the Voxzogo franchise's peak sales estimate.

Sponsor record: 13 of 70 late-stage studies registered by BioMarin Pharmaceutical were stopped early. Trials stop for many reasons — see the company profile for each one.

Program confirmed on ClinicalTrials.gov · 2026-09-05 · the date itself is unverified

IMpactMF Phase 3 interim analysis for imetelstat in myelofibrosis

Rytelo (imetelstat) · JAK-inhibitor relapsed/refractory myelofibrosis

Geron's first telomerase inhibitor is already approved in MDS. IMpactMF tests whether imetelstat can extend overall survival in myelofibrosis after JAK inhibitor failure — a setting with no approved options.

Survival hazard ratio below 0.7 would support an sNDA filing and approximately double the commercial opportunity for Rytelo. A wash would cap the asset at its current MDS-only ceiling.

Unverified — date is AI-generated and has not been checked against a primary source.

DESTINY-Breast09 Phase 3 OS update at ASCO 2026

Enhertu (trastuzumab deruxtecan) · 1L HER2+ metastatic breast cancer

AZN and Daiichi present mature overall survival data for Enhertu in front-line HER2+ metastatic breast cancer at ASCO. Confirming an OS advantage over the THP regimen would entrench Enhertu as the new 1L standard of care.

Updated OS hazard ratio with longer follow-up. Even a modest OS benefit (HR <0.85) supports continued guideline adoption. Watch for cardiac and pulmonary safety updates.

Program confirmed on ClinicalTrials.gov · 2026-09-09 · the date itself is unverified

Phase 3 IGNYTE-3 Phase 3 topline data in PD-1 failed melanoma

RP1 (vusolimogene oncorepvec) · Anti-PD-1 failed advanced melanoma

Replimune's oncolytic virus immunotherapy RP1 faces its definitive Phase 3 readout following the 2025 FDA CRL. A statistically robust ORR and DOR in the post-PD-1 melanoma setting clears the path back to FDA submission.

Phase 2 data showed 32-33% objective response rate. Phase 3 needs to confirm at least a 25% ORR with durable responses. Success doubles or triples REPL; failure caps the stock indefinitely.

Unverified — date is AI-generated and has not been checked against a primary source.

Amtagvi label expansion data update at ASCO 2026

Amtagvi (lifileucel) · Anti-PD-1 failed advanced melanoma; expansion into NSCLC

Iovance presents updated TIL therapy data including the first meaningful Phase 2 NSCLC dataset. NSCLC expansion is critical to scaling TIL beyond a melanoma niche.

Watch for response rate, durability, and manufacturing success rate in NSCLC. A confirmed response rate above 20% with manageable safety would meaningfully expand IOVA's TAM.

Sponsor record: 3 of 13 late-stage studies registered by Iovance Biotherapeutics were stopped early. Trials stop for many reasons — see the company profile for each one.

Unverified — date is AI-generated and has not been checked against a primary source.