8-K: Corbus Pharmaceuticals Announces Positive Phase 1 Data for Nectin-4 Targeting ADC at ASCO 2024

Corbus Pharmaceuticals' partner, CSPC Pharmaceutical Group, presented encouraging Phase 1 clinical trial data for SYS6002 (CRB-701), a next-generation Nectin-4 targeting antibody-drug conjugate, at the ASCO Annual Conference.

Summary

• Corbus Pharmaceuticals announced data from an ongoing Phase 1 clinical trial for SYS6002 (CRB-701), conducted by their development partner, CSPC Pharmaceutical Group.
• The data was presented at the American Society of Clinical Oncology (ASCO) Annual Conference on June 1, 2024.
• The Phase 1 dose escalation study is being conducted in China, enrolling patients with advanced solid tumors who have failed or were intolerant to standard treatment.
• The study enrolled patients based on Nectin-4 staining, except for metastatic urothelial cancer (mUC) patients who were considered Nectin-4 positive.
• Data presented is through April 2024 from 25 patients across seven dose levels (0.2 to 4.5 mg/Kg Q3W).
• SYS6002 (CRB-701) showed a 44% overall response rate (ORR) and 78% disease control rate (DCR) in mUC (n=9) and a 43% ORR and 86% DCR in cervical cancer (n=7).
• For all tumor types combined at doses of 2.7 mg/Kg and above, the ORR was 40% and DCR was 73% (n=15).
• The drug was generally well-tolerated with mainly grade 1 or 2 adverse events (AEs).
• No dose-limiting toxicities (DLTs) or grade 4 or 5 AEs have been observed to date.
• Early pharmacokinetic data shows lower levels of free MMAE compared to enfortumab vedotin across all doses.

Sentiment

Score: 8

Explanation: The document presents very positive clinical data for CRB-701, with strong efficacy signals and a favorable safety profile compared to existing treatments. The management commentary is also optimistic, suggesting a high level of confidence in the drug's potential.

Positives

• The drug shows promising efficacy with high response rates in mUC and cervical cancer.
• The safety profile is favorable, with mainly grade 1 or 2 adverse events and no DLTs or grade 4/5 AEs.
• Lower levels of free MMAE compared to enfortumab vedotin suggest a potentially improved safety profile.
• The study has progressed to higher dose levels without encountering significant safety issues.
• The drug is administered on a Q3W schedule, which could improve patient convenience and compliance.

Negatives

• Some patients experienced grade 3 skin rash and corneal disorders, although these were generally manageable.
• Anemia and eye-related treatment emergent AEs were the most common.
• One patient experienced peripheral neuropathy associated with hypokalemia, which resolved with treatment.

Risks

• The study is still in Phase 1, and further trials are needed to confirm these results.
• The long-term safety and efficacy of the drug are not yet fully established.
• The drug is being developed in partnership with CSPC, which introduces some reliance on their operations.
• There is a risk of unexpected adverse events as the study progresses to larger patient populations.
• The competitive landscape for Nectin-4 targeting ADCs is evolving, and the drug's success is not guaranteed.

Future Outlook

The corresponding US clinical study is progressing well and is expected to be on schedule for completion in Q4 with data presentation in Q1 2025. The company believes the emerging dataset positions CRB-701 to be a differentiated Nectin-4 ADC.

Management Comments

• Dr. Dominic Smethurst, Chief Medical Officer at Corbus, stated that the larger set of patient data, along with additional confirmed responses, increases confidence that CRB-701 is clinically active.
• Dr. Smethurst also noted that the emerging safety data is reassuring with low rates of skin rash and peripheral neuropathy.
• Dr. Yuval Cohen, Chief Executive Officer at Corbus, said they are encouraged by the latest data release.

Industry Context

This announcement is significant as it provides an update on a next-generation Nectin-4 targeting ADC, a class of drugs that is gaining attention in oncology. The data suggests that CRB-701 may offer a differentiated safety and efficacy profile compared to existing Nectin-4 ADCs like enfortumab vedotin (Padcev).

Comparison to Industry Standards

• The document compares CRB-701 to enfortumab vedotin (Padcev), a currently approved Nectin-4 ADC, highlighting CRB-701's lower levels of free MMAE and less frequent dosing schedule (Q3W vs. Padcev's Q1W).
• Padcev has a higher rate of serious adverse events (47%), dose interruptions (61%), and dose reductions (34%) compared to the early data for CRB-701.
• Padcev is associated with skin toxicities and peripheral neuropathy, which are also seen with CRB-701 but at lower rates.
• Other Nectin-4 ADCs like BT8009 and 9MW-2821 are mentioned, with CRB-701 showing a potentially more favorable safety profile in terms of grade 3 adverse events, peripheral neuropathy, and skin reactions.
• The document notes that Padcev's duration of response is approximately 5 months, which provides a benchmark for CRB-701's future performance.

Stakeholder Impact

• Shareholders: The positive clinical data is likely to be viewed favorably by investors, potentially increasing the company's stock value.
• Patients: The drug offers a potential new treatment option for patients with advanced solid tumors, particularly mUC and cervical cancer.
• Employees: The positive results may boost employee morale and confidence in the company's pipeline.
• Partners: The success of the partnership with CSPC is likely to strengthen the relationship and open up further collaboration opportunities.

Next Steps

• Continue dose escalation in the ongoing Phase 1 study.
• Expand PK cohorts at 2.7 and 3.6 mg/Kg.
• Determine the maximum tolerated dose (MTD) or recommended Phase 2 dose (RP2D).
• Initiate specific expansion cohorts.
• Complete the US dose escalation study by Q4 2024.
• Present US dose escalation data in Q1 2025.

Key Dates

Keywords

Nectin-4, Antibody Drug Conjugate, ADC, SYS6002, CRB-701, Oncology, Cancer, Clinical Trial, Phase 1, ASCO, Metastatic Urothelial Cancer, Cervical Cancer, MMAE, CSPC Pharmaceutical Group