Stock Markets May 26, 2026 09:00 AM

Corbus Shares Slide After CRB-701 Phase 1/2 Update

Updated efficacy and safety figures for the Nectin-4 antibody-drug conjugate coincide with a premarket drop as the company advances toward a registrational trial

By Jordan Park CRBP

Corbus Pharmaceuticals saw its shares fall 9.6% in premarket trading after releasing updated Phase 1/2 data for CRB-701, a Nectin-4 targeted antibody-drug conjugate. The April 1, 2026 data cut includes confirmed objective response rates in second-line oropharyngeal squamous cell carcinoma and second-line cervical cancer at the 3.6 mg/kg dose, along with detailed safety findings and the companys plan to initiate a registrational study in summer 2026 following broad alignment with the FDA on trial design.

Corbus Shares Slide After CRB-701 Phase 1/2 Update
CRBP

Key Points

  • Corbus shares fell 9.6% in premarket trading after release of updated Phase 1/2 data for CRB-701.
  • At the 3.6 mg/kg dose, CRB-701 produced confirmed ORRs of 42.9% in second-line oropharyngeal squamous cell carcinoma and 34.4% in second-line cervical cancer, with reported median durations of response and PFS values.
  • The Phase 1/2 data cut dated April 1, 2026 covered a safety population of 317 patients; Corbus plans to start a registrational, randomized 250-patient study in second-line oropharyngeal squamous cell carcinoma in summer 2026 after broad alignment with the FDA.

Market reaction and overview

Corbus Pharmaceuticals Holdings, Inc. (NASDAQ:CRBP) experienced a 9.6% decline in premarket trading Tuesday after it released updated efficacy and safety data from the ongoing Phase 1/2 study of CRB-701, its Nectin-4-directed antibody-drug conjugate.

Efficacy results from the April 1, 2026 data cut

The company reported results derived from a data cut on April 1, 2026. At the 3.6 mg/kg dose level, CRB-701 produced a confirmed objective response rate (ORR) of 42.9% in second-line oropharyngeal squamous cell carcinoma, with a median duration of response of 6.3 months and a median progression-free survival (PFS) of 5.6 months. In second-line cervical cancer at the same dose, the confirmed ORR was 34.4%, with a median duration of response of 8.0 months and median PFS of 4.3 months.

Study population and data scope

The Phase 1/2 program's safety population comprised 317 patients overall. Within that population, 75 patients with head and neck squamous cell carcinoma were enrolled across the 2.7 mg/kg and 3.6 mg/kg dose cohorts, and 72 patients with cervical cancer were enrolled across those same doses.

Safety profile

CRB-701's reported safety profile included treatment discontinuations attributed to the drug at 2.8%. The most frequently observed treatment-related adverse events listed were keratitis at 49.2%, alopecia at 25.6%, fatigue at 22.4%, and dysgeusia at 19.9%. Grade 3 adverse events occurred in 19.2% of patients, and Grade 4 adverse events were reported in 0.9% of patients.

Regulatory path and next steps

Corbus said it remains on schedule to start a registrational study of CRB-701 in second-line oropharyngeal squamous cell carcinoma in summer 2026. The company reported it had reached broad alignment with the U.S. Food and Drug Administration on the design of a randomized controlled trial expected to enroll 250 patients.

Implications for markets and sectors

The updated dataset coincided with immediate market movement in Corbus shares. The information will be of interest to investors focused on biotechnology and healthcare equities, as well as market participants tracking oncology pipelines and clinical development milestones.

What remains in focus

Key upcoming items include the planned initiation of the registrational trial in summer 2026 and execution of the randomized 250-patient study aligned with the FDA. The companys published safety and efficacy figures from the April 1, 2026 data cut will form the basis for that next-stage study.


Data reported in this article are those provided by the company in its updated Phase 1/2 release and are presented without additional interpretation beyond the information disclosed.

Risks

  • Safety events are notable in the dataset, including keratitis reported in 49.2% of patients and Grade 3 adverse events in 19.2% of patients - risks that affect clinical tolerability and development decisions in the biotech and healthcare sectors.
  • Subgroup sample sizes cited - 75 head and neck squamous cell carcinoma patients and 72 cervical cancer patients enrolled at the 2.7 mg/kg and 3.6 mg/kg doses - limit the breadth of the efficacy readout and represent an uncertainty for market and development expectations.
  • Market reaction to the data has already affected the company's equity, evidenced by the 9.6% premarket decline, introducing volatility risk for investors in biotech and healthcare equities.

More from Stock Markets

Toronto market ends at fresh record as healthcare, financials and materials lead gains Jun 4, 2026 After-Hours Movers: Lululemon Dips on Guidance as Software and Data Names Show Mixed Reactions Jun 4, 2026 Lululemon Lowers Fiscal 2026 Revenue and EPS Guidance as U.S. Demand Softens Jun 4, 2026 Anthropic Places Engineers Inside NSA to Support Mythos AI for Offensive Cyber Tasks Jun 4, 2026 Trump Directs $700M Toward Coal Industry, Lifting Peabody Shares Jun 4, 2026