Corbus Pharmaceuticals (CRBP) Study update summary

Study design and patient characteristics

• CRB-701 evaluated in Phase 1/2 studies in the US and Europe, enrolling 317 patients across all tumor types and doses, including 75 with HNSCC and 72 with cervical cancer at 2.7 mg/kg and 3.6 mg/kg.

• Efficacy-evaluable populations included 71 HNSCC and 70 cervical cancer patients.

• OPSCC subset had a high prevalence of HPV positivity (85.4%), aligning with epidemiological trends.

• Cervical cancer cohort had a median age of 54, all female, with a median of 3 prior therapies.

• April 1st data cut presented at ASCO focused on head and neck (oropharyngeal) and cervical cancers at two relevant doses, with emphasis on the 3.6 mg/kg dose.

Safety and tolerability

• Safety profile remains consistent, with few Grade 3 (19.2%) and very few Grade 4 (0.9%) events, and no Grade 5 events.

• Peripheral neuropathy rates were low (7.3%, all grade 1/2), with no grade >3 events.

• Skin toxicity was mostly mild, with only one Grade 3 event and no severe cases like SJS or TEN.

• Ocular toxicities were primarily Grades 1 and 2, with Grade 3 just above 10%, a single reversible Grade 4, and discontinuations due to ocular AEs at 1.9%.

• Discontinuation rates for toxicity were low (2.8%) and have improved since previous data cuts.

Efficacy in head and neck (oropharyngeal/OPSCC) cancer

• In 2L OPSCC at 3.6 mg/kg, confirmed ORR was 42.9%, DCR 85.7%, median DOR 6.3 months, and PFS 5.6 months (ongoing).

• Efficacy in HPV+ OPSCC was particularly high, with 89% of responders being HPV positive.

• Non-OPSCC HNSCC showed lower efficacy: CORR 0%, DCR 62.5%, PFS 2.7 months.

• Durability of response in oropharyngeal patients now exceeds six months.

• The study does not require HPV+ status for enrollment, only anatomical oropharyngeal definition.