August 2026 Biotech Catalysts: 4 PDUFAs, 2 Ghosts, Ranked

The August 2026 FDA calendar looks packed at first glance. Six PDUFA dates spanning oncology, vaccines, rare disease, and HIV. But when you actually read the details, two of those dates are ghosts: catalysts that have already been consumed or moved. The remaining four split into one genuine small-cap binary event and three mega-cap events where the stock will not move regardless of the outcome. If you are planning August trades around the Q3 FDA calendar, this is what is actually investable.

Update August 31, 2026: NVO Mim8 is now 23 business days past its July 29 PDUFA — still unapproved, with Drugs.com listing “FDA Approved: No.” and no Novo Nordisk press release. NVO closed at $45.61 on August 28 (Polygon).

Update August 28, 2026: Gilead’s Bixlenvo (BIC/LEN) was approved August 27 on its PDUFA date — the first once-daily single-tablet regimen for virologically suppressed adults with HIV on complex regimens (see our Bixlenvo coverage). GILD closed at $148.86, up 0.52%. NVO Mim8 is now 22 business days past its July 29 PDUFA.

Update August 27, 2026: JAZZ Ziihera was approved on its August 25 PDUFA for first-line HER2+ GEA — see our breaking coverage. ROIV brepocitinib (LISRAYA) was approved August 27 for dermatomyositis — see our breaking coverage. NVO Mim8 is now 21 business days past its July 29 PDUFA.

Update August 25, 2026: CAPR deramiocel — the FDA confirmed on August 24 that it extended the PDUFA to November 22, 2026, a three-month major-amendment extension to review Capricor’s upper-limb-only data (see our amendment coverage). NVO Mim8 is now 19 business days past its July 29 PDUFA. JAZZ Ziihera PDUFA is today (Aug 25) and GILD BIC/LEN follows Aug 27.

Update August 22, 2026: The August catalyst map has shifted. NVO Mim8 PDUFA (July 29) is now 17 business days overdue — the longest Q3 delay by far; NVO closed at $46.14 on August 20 (Polygon). CAPR deramiocel PDUFA (Aug 22) has now arrived; on August 21 Capricor confirmed a BLA amendment narrowing deramiocel to an upper-limb-only claim, with the FDA expected to extend the PDUFA once it receives the amendment — see our amendment coverage. CAPR surged 67% after-hours on August 13 on the pivot, closing at $6.84 on August 20, though STAT reports the FDA is “heading for” rejection. The biggest August catalyst was unanticipated at publication: Moderna’s intismeran cancer vaccine cleared Phase 3 INTerpath-001 on August 19 and MRNA surged 177% — see our breaking coverage. GILD at $143.44 (PDUFA Aug 27) and JAZZ at $248.70 (PDUFA Aug 25) remain pending as mega-cap non-events.

1. Replimune (REPL) | $12.86 | Market Cap ~$1.1B | PDUFA August 2 — APPROVED August 6

The FDA granted accelerated approval to Tudriqev (vusolimogene oderparepvec-wtpg, formerly RP1) on August 6, 2026, in combination with nivolumab for adults with unresectable advanced cutaneous melanoma who progressed on an anti-PD-1 regimen. This was Replimune’s third BLA submission after two prior CRLs (July 2025 and April 2026). The CTGTAC advisory committee voted 10-3 in favor on July 30 despite FDA briefing documents that called the IGNYTE study “not interpretable.”

At the pre-approval trough, REPL fell to $5.35 on July 29 before the AdComm vote. The stock surged to $12.86 by the August 6 approval close, a 140% gain in 8 days. The approval is the first oncolytic virus immunotherapy for melanoma. Continued approval is contingent on the confirmatory Phase 3 IGNYTE-3 trial. See our Tudriqev approval coverage and the pre-approval PDUFA tracking article.

2. Moderna (MRNA) | $55.81 | Market Cap $22.1B | PDUFA August 5 | First mRNA Flu Vaccine — APPROVED

mRNA-1010 (mFLUSIVA) was approved by the FDA on August 5, 2026, making it the first mRNA-based seasonal influenza vaccine licensed in the US. The VRBPAC voted 9-0 on June 18, 2026 that benefits outweigh risks for adults 50 and older. The approval covers standard use in adults 50-64 and accelerated approval for ages 65 and older with a postmarketing confirmatory trial required. It will be available for the 2026 to 2027 flu season.

The Phase 3 trial enrolled 40,703 adults across 301 sites in 11 countries. mRNA-1010 showed 26.6 percent relative vaccine efficacy versus standard-dose flu shots (2.0 percent versus 2.8 percent influenza incidence). The rVE was consistent across strains: 29.6 percent against A/H1N1, 22.2 percent against A/H3N2, and 29.1 percent against B/Victoria. In the 19,260 participants aged 65 and older, rVE was 27.4 percent. The full Phase 3 results were published in the New England Journal of Medicine.

At $22.1 billion market cap, this approval validates the platform but is immaterial to Moderna’s stock. The flu vaccine market is approximately $7 billion globally. Even if mRNA-1010 captures 10 percent market share, that is $700 million in revenue against Moderna’s $4.5 billion 2025 base. The stock has been trading on COVID franchise erosion and the cancer vaccine platform, not on flu. The 9-0 AdComm vote telegraphed approval, so the stock reaction was muted as expected. Moderna remains a show-me story on the mRNA platform.

3. Gilead (GILD) | $148.86 | Market Cap ~$185B | PDUFA August 27 — APPROVED August 27 | BIC/LEN HIV NDA (Bixlenvo), Mega-Cap Immaterial

Bictegravir 75 mg plus lenacapavir 50 mg (BIC/LEN) is a once-daily single-tablet HIV regimen for virologically suppressed adults. The FDA granted Priority Review with an August 27 PDUFA. The NDA is supported by two Phase 3 trials (ARTISTRY-1 and ARTISTRY-2) where BIC/LEN was non-inferior to comparator regimens at Week 48. In ARTISTRY-1, 0.8% of BIC/LEN participants had HIV-1 RNA ≥50 copies/mL versus 1.1% on complex multi-tablet regimens. In ARTISTRY-2, 1.3% versus 1.0% on Biktarvy. No significant safety signals were identified.

Gilead is the HIV franchise leader. Biktarvy generated $14 billion in 2025 revenue. BIC/LEN would be a next-generation option for patients seeking a simpler regimen or those with resistance concerns. But at $166.8 billion market cap, even a $500 million peak sales drug moves the needle by 0.3 percent of revenue. The stock will not react to this approval. We previously analyzed the ISL/LEN weekly HIV program and the lenacapavir PrEP approval. Gilead is a Hold regardless of the BIC/LEN outcome.

4. Jazz Pharmaceuticals (JAZZ) | $256.92 | Market Cap $16.1B | PDUFA August 25 — APPROVED August 25 | Ziihera sBLA for First-Line GEA

Ziihera (zanidatamab-hrii) is already approved for previously treated HER2-positive biliary tract cancer under accelerated approval. The FDA approved Ziihera on its August 25 PDUFA date for first-line HER2-positive gastroesophageal adenocarcinoma (GEA), a label expansion based on the HERIZON-GEA-01 Phase 3 trial. See our approval coverage. Both Ziihera plus chemotherapy and Ziihera plus tislelizumab plus chemotherapy demonstrated statistically significant PFS improvements over trastuzumab plus chemotherapy. The Ziihera plus tislelizumab arm also showed statistically significant overall survival improvement. Confirmed ORRs were 70.7 percent and 69.6 percent in the two Ziihera arms versus 65.7 percent in the control arm.

The GEA market is approximately 20 percent HER2-positive of 1 million new cases globally, meaning roughly 200,000 eligible patients. That is a meaningful label expansion from the 12,000-patient BTC population. But Jazz is a $16.1 billion company with $3.8 billion in 2025 revenue. Ziihera’s current BTC revenue is modest. Even with GEA expansion, Ziihera peak sales of $500 million to $800 million by 2029 would add 13 to 21 percent to revenue. The stock moves 3 to 5 percent on approval, not 20 percent.

Ghost Catalyst 1: Merck KEYTRUDA QLEX (Aug 17) | Already Approved July 10

The brief lists an August 17 PDUFA for KEYTRUDA QLEX in combination with Padcev for muscle-invasive bladder cancer. The FDA already approved the Padcev-Keytruda MIBC combination on July 10, 2026, five weeks ahead of the PDUFA date. The catalyst is consumed. MRK at $325.6 billion market cap would not have moved on this approval regardless, but the August 17 date is now a non-event. Do not plan a trade around it.

Ghost Catalyst 2: Savara MOLBREEVI (Aug 22) | PDUFA Moved to November 22

The brief lists an August 22 PDUFA for MOLBREEVI (molgramostim) in autoimmune pulmonary alveolar proteinosis (aPAP). The FDA extended the review period by three months to November 22, 2026, after determining that Savara’s responses to information requests constituted a major amendment to the BLA. The IMPALA-2 Phase 3 trial showed a 6.0 percentage point treatment difference in DLCO change at Week 24 (p<0.001) and an 80.6 meter improvement in 6-minute walk distance at Week 48 (p=0.03). The data is solid. The date just moved. This is a November catalyst now, not an August one.

Risks and Position Sizing

Every pre-PDUFA trade carries CRL risk. The historical CRL base rate is approximately 37 percent. For Replimune specifically, the risk is elevated: two prior CRLs, FDA briefing documents questioning the trial design, and an AdCom where the FDA staff already signaled skepticism. A 2 to 5 percent portfolio allocation per pre-PDUFA play is the maximum prudent size. For the mega-cap catalysts (MRK, GILD, JAZZ), position sizing is irrelevant because the stock will not move enough to matter. For the three-window FDA catalyst trading framework, the entry window for August catalysts is already closing. You are late if you are entering now.

The Verdict: One Trade, Three Watches, Two Ghosts

Ranked by stock-moving potential:

1. Replimune (REPL) | Approved. The FDA granted accelerated approval to Tudriqev on August 6, 2026. The stock went from $5.35 (pre-AdCom trough on July 29) to $12.86 on the August 6 approval close — a 140% gain. The only August small-cap binary has been resolved. At ~$1.1B market cap post-approval, the catalyst has played out. The confirmatory IGNYTE-3 Phase 3 trial is now a post-marketing requirement.

2. Jazz (JAZZ) | Approved. The FDA approved Ziihera for first-line HER2+ GEA on August 25, as expected. JAZZ rose about 3.5% to roughly $263, matching the “3 to 5 percent on approval” expectation. The label expansion is commercially meaningful but at a $16.1B market cap it is not a stock-moving event. See our approval coverage.

3. Moderna (MRNA) | Watch — Approved. The FDA approved mFlusiva on August 5, 2026, making it the first mRNA-based seasonal flu vaccine licensed in the US. The VRBPAC voted 9-0 on June 18 and the decision came on time. The approval covers adults 50-64 (standard) and 65+ (accelerated with postmarketing requirement). At $22.1B market cap, this approval validates the mRNA platform beyond COVID but is immaterial to the stock’s near-term financials. The flu vaccine market is approximately $7 billion globally and even 10% market share ($700M) is a fraction of Moderna’s revenue base. The real Moderna catalyst remains the cancer vaccine program, not the flu franchise. Buy the dips on platform validation, not the approval headline.

4. Gilead (GILD) | Approved. The FDA approved Bixlenvo (BIC/LEN) on August 27, its PDUFA date. GILD closed at $148.86, up 0.52% — exactly the non-event this article predicted for a mega-cap. BIC/LEN is a franchise extension, not a franchise maker. Own Gilead for the HIV pipeline and lenacapavir PrEP, not for this specific PDUFA. See our Bixlenvo coverage.

5. Merck (MRK) | Ghost. Already approved. Catalyst consumed. Move on.

6. Savara (SVRA) | Ghost. Moved to November 22. The best biotech stocks ranking already covers SVRA as a November catalyst. Come back in October.

The contrarian call: the market had priced Replimune for a third CRL after the 48 percent crash to $5.35. The 10-3 AdComm vote and subsequent accelerated approval validated the thesis that the IGNYTE data was clinically meaningful despite the FDA staff’s “not interpretable” assessment. At $12.86 on the August 6 close, the stock has repriced for approval at ~$1.1B market cap. The play now is the commercial launch and IGNYTE-3 confirmatory data, not the PDUFA binary.