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# ArriVent Beat the Chemotherapy Arm It Designed and Lost to the Referee It Chose
- URL: https://bioweek.com/arrivent-beat-the-chemotherapy-arm-it-designed-and-lost-to-the-referee-it-chose/
- Published: 2026-10-07T05:07:17.000Z
- Updated: 2026-10-07T05:07:17.000Z
- Description: ArriVent's firmonertinib beat chemotherapy on investigator reads in a 398-patient Phase 3, but the blinded central review it chose returned p=0.0654, and first-line EGFR exon 20 lung cancer now belongs to combinations that keep chemotherapy in the regimen.
- Author: BioWeek
- Tags: Pipeline, Science

Firmonertinib did, in a narrow sense, what a first-line EGFR exon 20 insertion inhibitor is supposed to do. Patients on 240 milligrams lasted a median 11.0 months without progression, against 9.5 months on platinum chemotherapy plus pemetrexed. The hazard ratio was 0.75\. The p-value was 0.0654\. That last number is why ArriVent BioPharma (Nasdaq: AVBP) [reported](https://www.stocktitan.net/sec-filings/AVBP/8-k-arri-vent-bio-pharma-inc-reports-material-event-36613dd8ce66.html?ref=bioweek.com) a miss on Phase 3 FURVENT on October 6, why CEO Bing Yao called the results disappointing, and why the stock opened down 57 percent at $12.37.

The same dataset holds a second story. Investigators watching the same 398 patients saw 11.1 months of progression-free survival on 240 milligrams versus 7.1 months on chemotherapy, a hazard ratio of 0.61 (95% CI 0.46-0.81). Confirmed objective response by blinded independent central review was 60 percent versus 33 percent. Overall survival is immature and already trends the company's way. The drug beat the chemotherapy arm ArriVent designed. It failed the referee it chose.

### Two clocks, one p-value

FURVENT randomized previously untreated patients with locally advanced or metastatic non-squamous NSCLC and EGFR exon 20 insertions across three arms: 240 milligrams, 160 milligrams, and platinum-pemetrexed. The trial ran globally with partner Allist. The primary endpoint was progression-free survival by BICR, not by site investigators.

At 240 milligrams, BICR median PFS was 11.0 months versus 9.5 months, HR 0.75 (95% CI 0.55-1.02), p=0.0654\. The 160 milligram arm fell short at 8.4 months, HR 0.91 (0.67-1.25). Investigator assessment restored a conventional win at the higher dose. Grade 3 or higher treatment-emergent events ran 52 percent at 240 milligrams, 53 percent at 160 milligrams, and 55 percent on control. Grade 3 or higher treatment-related events were 26 percent, 22 percent, and 40 percent. No new signals appeared.

### The control arm that would not sit still

Guggenheim Securities, in an April note cited by Fierce, observed that sponsors of recent Phase 3 trials in this setting had all assumed 5 to 7 months of median PFS on chemotherapy. FURVENT's control arm delivered 9.5\. BTIG's Jeet Mukherjee, in trade [reporting](https://tickergrove.com/stories/arrivent-firmonertinib-furvent-phase-3-miss-20261006?ref=bioweek.com), put the miss more tightly: chemotherapy came in at 9.5 months against an expected 7.5 to 8, while firmonertinib's 11 months sat inside the 9 to 11 window the Street had already modeled.

That is a known hazard of open-label oncology studies with a BICR primary. Investigators, seeing an oral targeted drug against intravenous chemotherapy, may call progression earlier on the control arm; central reviewers, blinded to treatment, do not. FURVENT's 2.4-month gap between investigator control PFS (7.1 months) and BICR control PFS (9.5 months) is the gap that swallowed the p-value. Shares closed October 6 at $15.09, down about 47 percent, per market [data](https://exa.ai/library/markets/stock/AVBP?ref=bioweek.com).

### A first-line market that has already moved on

Even a BICR win would have landed in a changed field. Johnson & Johnson's Rybrevant (amivantamab-vmjw) plus chemotherapy was [approved](https://www.jnj.com/media-center/press-releases/rybrevant-amivantamab-vmjw-in-combination-with-chemotherapy-is-the-first-fda-approved-therapy-for-first-line-treatment-of-patients-with-non-small-cell-lung-cancer-with-egfr-exon-20-insertion-mutations?ref=bioweek.com) on March 1, 2024 as the first FDA-cleared first-line therapy for EGFR exon 20 insertion NSCLC. PAPILLON, the approval basis [published](https://www.nejm.org/doi/full/10.1056/NEJMoa2306441?ref=bioweek.com) in NEJM on October 21, 2023, showed a BICR hazard ratio for progression or death of 0.40 (95% CI 0.30-0.53), P<0.001\. J&J reported median PFS of 11.4 months on the combination versus 6.7 months on chemotherapy alone.

One month before FURVENT, the add-on strategy posted a cleaner interim. On September 13, Cullinan and Taiho [disclosed](https://app.edgar.tools/filing/1789972/0001193125-26-389844/cgem-ex99%5F1.htm?ref=bioweek.com) that zipalertinib plus chemotherapy met REZILIENT3 at the planned look: median PFS 14.5 months versus 8.5 months, HR 0.50 (0.34-0.73), P=0.00015, in 279 randomized patients, with confirmed response of 65.0 percent versus 40.3 percent. Interim overall survival, at 30 percent maturity, was HR 0.72 (0.42-1.23). The designs are not interchangeable: zipalertinib is layered on chemotherapy, and firmonertinib was tested as a replacement for it. Cross-trial comparisons are not direct, though payers and oncologists will make them anyway. Exon 20 insertions are about 9 percent of EGFR mutations.

### What is left to argue

ArriVent said it is evaluating the full FURVENT dataset to determine the most appropriate development path, with no decision announced. Overall survival could yet move if the immature trend holds, though a missed PFS primary is a hard substrate for a first-line label. Firmonertinib already holds FDA Breakthrough Therapy Designation in this first-line exon 20 setting, is approved in China for first-line classical EGFR mutations and for post-platinum exon 20 insertions, and has a second pivotal study, ALPACCA (NCT07185997), underway in first-line NSCLC with EGFR PACC mutations. That trial is now the company's remaining Phase 3 bet.

Cash and investments were $373.1 million as of June 30, 2026, a runway the company [said](https://www.globenewswire.com/news-release/2026/08/12/3344035/0/en/arrivent-biopharma-reports-second-quarter-2026-financial-results.html?ref=bioweek.com) should fund operations into 2028, after $81.5 million of operating cash use and $80.0 million of R&D in the first half. Runway is not the problem. What ArriVent lacks is a registrable first-line exon 20 story.

The open question is whether an 11.0-month BICR median, a 60 percent response rate, and a friendlier toxicity profile than platinum can be repositioned around a p-value of 0.0654, in a market that already has an approved chemo combination and a rival add-on that just cleared its interim. ArriVent beat chemotherapy. The referee, and the field, did not agree that was enough.