The Ghost PDUFA Date: Zidesamtinib Was Approved Two Months Early, After Nuvalent Was Already Sold

· 6 min read

If your catalyst calendar still shows a September 18, 2026 PDUFA date for Nuvalent’s zidesamtinib, it is showing a date that no longer means anything. Two things happened first. GSK’s $124.00 per share cash tender offer for Nuvalent closed on July 15, 2026 and the stock stopped trading (Nuvalent 8-K, July 15, 2026). One week later, on July 22, 2026, the FDA approved zidesamtinib under the brand name Jideytro, eight weeks ahead of the goal date (FDA, July 22, 2026).

We are writing this partly as a correction. Until this week BioRadar’s own calendar listed the September 18 date as pending, with a probability-of-approval score attached, because our pipeline only reconciled a decision after its date had passed. This piece sets out what happened, why the approval came early, what the label actually says, and what we changed so that a ghost date does not sit on our pages again.

The non-obvious point for anyone who trades FDA dates: a PDUFA date is a deadline, not an event. The decision can arrive early, and the stock you planned to trade can disappear before either.

What happened, in order

Date Event Source
February 27, 2024 FDA grants Breakthrough Therapy designation to NVL-520 (zidesamtinib) for ROS1-positive NSCLC after two or more prior ROS1 TKIs Nuvalent press release
June 24, 2025 Pivotal ARROS-1 data; pre-NDA meeting completed; rolling submission begins under Real-Time Oncology Review Nuvalent press release
September 19, 2025 NDA 220185 received by FDA FDA approval letter
November 19, 2025 NDA accepted for filing; PDUFA target action date September 18, 2026 Nuvalent press release
June 9, 2026 GSK agrees to acquire Nuvalent for $124.00 per share in cash, about $10.6 billion in equity value, a 40% premium GSK release; Nuvalent 8-K
July 14, 2026 Tender offer expires with 72,518,967 shares tendered, 91.3% of those outstanding Nuvalent 8-K
July 15, 2026 Merger completes; NUVL shares cease trading Nuvalent 8-K
July 22, 2026 FDA approves Jideytro (zidesamtinib) FDA approval letter
July 27, 2026 Form 15 filed, terminating SEC registration of the shares Nuvalent Form 15
September 18, 2026 The original goal date. Nothing is scheduled to happen.

Why the approval came early

The September 18 goal date was twelve months after the September 19, 2025 receipt date, which is the standard-review clock; Drugs@FDA lists the review priority as standard, the submission as a Type 1 new molecular entity, and the product as carrying orphan drug designation (Drugs@FDA, NDA 220185). The approval landed at ten months.

The review ran under the FDA’s Real-Time Oncology Review pilot with an Assessment Aid, and the application was not referred to an advisory committee because, in the agency’s words in the approval letter, it did not raise significant issues (FDA approval notice and approval letter, July 22, 2026). Real-Time Oncology Review lets the agency assess components of an application as they are submitted rather than after the complete package arrives, which is why these reviews often finish ahead of the goal date. Breakthrough Therapy designation, granted in February 2024, adds intensive FDA guidance during development. None of this is visible in a calendar entry that shows only the deadline.

What the label says, and what it cannot say

The approved indication is adult patients with locally advanced or metastatic ROS1-positive NSCLC who have received a prior ROS1 kinase inhibitor (Jideytro prescribing information, July 2026). The pivotal dataset is ARROS-1, single-arm and open-label, with 117 TKI-pretreated patients assessed by blinded independent central review.

  • Confirmed objective response rate 44% (95% CI 34 to 53), with a complete response rate of 0.9% (label section 14.1).
  • 49% after one prior ROS1 TKI (n=59) and 38% after two or more (n=58).
  • Duration of response ranged from 1.9 to 28.5+ months; 69% of responders had responses lasting at least 12 months as an observed proportion. Nuvalent’s June 2025 release reported 78% at 12 months, but that was a Kaplan-Meier estimate at a March 21, 2025 cut-off, so the two figures are not the same measurement (Nuvalent, June 24, 2025; label section 14.1).
  • Intracranial response rate 48% among 50 patients with measurable CNS metastases; response rate 54% (14 of 26) in patients with the ROS1 G2032R resistance mutation (label section 14.1).

Two things the label cannot tell you. First, there is no randomized comparison, so any ranking against other ROS1 inhibitors is a cross-trial comparison between differently defined pretreated populations with follow-up that differs by years. We are deliberately not printing competitor numbers next to these. Second, the TKI-naive population is not in the label. Before the deal Nuvalent had guided to a submission for that expansion in the second half of 2026 (Nuvalent, February 26, 2026); whether GSK keeps that timing is not public. The label also carries a Warnings and Precautions entry for CNS adverse reactions, which is worth noting for a molecule designed to spare TRK.

The trade that never got to happen

BioRadar’s verified record of 35 FDA decisions (22 approvals, 13 Complete Response Letters) shows the familiar shape: approvals ran up an average of 15.6% in the 30 days before the decision and moved an average of -0.1% on the day itself, while CRLs fell an average of 13.7% on the day and 33.1% over five days (BioRadar data, small sample, see the historical PDUFA outcomes). Zidesamtinib never entered that distribution. From June 9 the shares were pinned to the $124.00 deal price, and their final trades printed within pennies of it (StockAnalysis price history).

The market had already answered a different question. Before the deal, Wall Street price targets ranged from $116.00 to $172.00 (Centerview’s fairness analysis in the Schedule 14D-9, June 24, 2026); GSK paid $124.00, about $10.6 billion in equity value and $9.4 billion net of cash (GSK, June 9, 2026). Financing was never the issue: Nuvalent held $1,287.5 million in cash and marketable securities at March 31, 2026 against $92.4 million of operating cash burn in the first quarter (Form 10-Q, May 7, 2026). Every officer and director disposed of their shares at $124.00 on July 15 under the merger agreement (Form 4 filings, July 2026). The regulatory event that calendars were built around became a footnote inside a large company.

Our own miss, and the fix

Our September 18 row came from Nuvalent’s own filings and was correct when it was created. It went stale because our reconciliation only looked backward: an event was checked against openFDA and dated headlines once its date had passed. Nothing looked at a pending date to ask whether it had already resolved. The row survived the deal announcement, the tender, the delisting and the approval, and it appeared in our weekly digest as an upcoming decision. We found it while researching this article.

Three changes. The row is now marked approved, the decision is archived under its real date, July 22, 2026, with the FDA approval letter as evidence, and the probability-of-approval score that was attached to it is gone. The pipeline now checks every pending date inside the next 75 days once a day against dated headlines, and only an explicit FDA-action headline (approval, Complete Response Letter, extension or withdrawal) can resolve a date early; we do not infer anything from price moves. And as the sample grows we will publish how often dates resolve before they arrive, because right now we do not have that base rate and will not invent one.

What is left to watch

Nuvalent’s second program, neladalkib for TKI-pretreated ALK-positive NSCLC, has an NDA under priority review with a PDUFA date of November 27, 2026 (Nuvalent, May 27, 2026). It now belongs to GSK, whose September 2026 Form 6-K confirms both the acquisition and the July approval (GSK 6-K, September 2026). For a company of GSK’s size that decision is not a tradable small-cap catalyst, which is another way a calendar entry can be technically correct and practically empty. The upcoming FDA decisions we track are now filtered by status, and the NUVL ticker page remains as a historical record.

Frequently asked questions

Was zidesamtinib approved?

Yes. The FDA approved zidesamtinib as Jideytro on July 22, 2026 for adult patients with locally advanced or metastatic ROS1-positive NSCLC who have received a prior ROS1 kinase inhibitor.

Why was it approved before the September 18, 2026 PDUFA date?

The review ran under the FDA’s Real-Time Oncology Review pilot, needed no advisory committee, and finished at ten months against a twelve-month standard-review goal. Early action is a known feature of that pathway.

Can NUVL still be traded around the September 18 date?

No. GSK’s tender offer at $124.00 per share closed on July 15, 2026, the shares were delisted, and Nuvalent filed a Form 15 on July 27, 2026 terminating its SEC registration.

What should PDUFA calendar traders take from this?

Treat the date as a deadline, not an event; check whether the sponsor is in a pending acquisition; and check the status of the entry, not just the date.

Sources

Disclosure: the author has no position in NUVL at publication. This is analysis of public data, not investment advice.

This data is for informational purposes only, not investment advice. BioRadar does not provide buy/sell recommendations. Past performance does not guarantee future results. Always do your own due diligence.