May 2026 Biotech Catalysts: 12 FDA Dates & Phase 3 Readouts

PDUFA decision date for resmetirom label expansion in pre-cirrhotic MASH

Rezdiffra (resmetirom) · Metabolic dysfunction-associated steatohepatitis (MASH)

The FDA decides whether to broaden Rezdiffra's label into earlier-stage liver disease. Madrigal already owns the first MASH approval; a broader label dramatically expands the eligible patient population and protects against incoming GLP-1 competition.

Approval likely given the F2/F3 NASH biopsy data already supporting the original approval. Watch the label language around fibrosis stage and biomarker-driven prescribing. Approval supports MDGL premium valuation; CRL knocks 25-40% off the stock.

PDUFA decision date for suzetrigine label expansion to chronic pain

Journavx (suzetrigine) · Chronic pain (DPN, lumbosacral radiculopathy)

Vertex's non-opioid pain drug Journavx is up for a major label expansion into chronic pain. Approved for acute pain in 2025, the chronic indication is the multi-billion dollar prize and the test of whether non-opioid analgesia can finally compete with opioids and gabapentinoids.

Phase 3 chronic pain data was mixed; approval probability is roughly 60/40. Approval would re-rate VRTX higher on a $5B+ chronic pain franchise. A CRL pushes the franchise back 12-18 months and likely costs 8-12% on the stock.

PDUFA decision date for SRP-9003 (LGMD2E gene therapy)

SRP-9003 (bidridistrogene xeboparvovec) · Limb-girdle muscular dystrophy type 2E (LGMD2E)

FDA decision on Sarepta's second muscular dystrophy gene therapy. After the Elevidys controversy, this approval is a referendum on whether FDA still trusts Sarepta's AAV gene therapy platform.

Patient numbers are small but unmet need is real. Approval likely but with restricted label. A second AdCom or CRL would severely damage SRPT's gene therapy platform credibility.

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).

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.

PDUFA decision date for elranatamab in earlier-line multiple myeloma

Elrexfio (elranatamab) · Multiple myeloma (2L+)

FDA decides whether to move Pfizer's BCMA bispecific Elrexfio into earlier lines of myeloma therapy. Earlier-line approval triples the addressable patient population and pressures J&J's Tecvayli.

Approval likely given the MagnetisMM-5 randomized trial showing PFS benefit over standard of care. Bigger question is the commercial uptake versus Tecvayli and the new GPRC5D bispecifics. Modest single-day stock impact on PFE; meaningful trajectory shift for the franchise.

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.

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.

PDUFA decision for roflumilast cream label expansion to pediatric AD

Zoryve (roflumilast) · Atopic dermatitis in children ages 2-5

Arcutis expands its topical PDE4 inhibitor into the pediatric atopic dermatitis market. Approval gives the franchise a meaningful new growth lever and a competitive moat in pediatric-friendly steroid-free topicals.

Approval highly likely given clean safety profile and successful Phase 3 INTEGUMENT-PED. Stock impact modest but the label is critical for the long-term franchise narrative.

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.

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.

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.