8-K: Sonnet BioTherapeutics' SON-080 Cleared for Phase 2 Trial After Positive Safety Review

Sonnet BioTherapeutics announced that its Phase 1b/2a clinical trial of SON-080 for chemotherapy-induced peripheral neuropathy has been cleared to proceed to Phase 2 after a positive safety review.

Summary

• Sonnet BioTherapeutics' Phase 1b/2a clinical trial for SON-080, a treatment for chemotherapy-induced peripheral neuropathy (CIPN), has successfully completed its initial safety review.
• The Data and Safety Monitoring Board (DSMB) has cleared the trial to move into Phase 2.
• The study, known as SB211, is being conducted in Australia and involves a new version of recombinant human Interleukin-6 (rhIL-6).
• The Phase 1b portion of the trial focused on the safety and tolerability of low doses of SON-080, up to 1 g/kg, administered subcutaneously three times a week for twelve weeks.
• The initial safety profile of SON-080 was consistent with previous studies of low-dose rhIL-6, with mild to moderate injection site reactions, fatigue, body aches, and nausea reported.
• One patient withdrew from the study due to severe fatigue.
• All adverse events were transient and reversible.
• The unblinded safety data from two dose levels of SON-080 compared to placebo are expected in the second half of 2024.
• The company plans to leverage the safety data to initiate a Phase 2 clinical trial in Diabetic Peripheral Neuropathy (DPN), a larger market opportunity, after securing a potential partnership.

Sentiment

Score: 8

Explanation: The document conveys a positive sentiment due to the successful completion of the Phase 1b safety review and the clearance to proceed to Phase 2. The focus on the larger DPN market and the initiation of a partnering process also contribute to the positive outlook. However, the withdrawal of one patient and the hold on CIPN development temper the sentiment slightly.

Positives

• The DSMB cleared the trial to proceed to Phase 2, indicating a positive safety profile for SON-080.
• The adverse events were mostly mild to moderate, transient, and reversible.
• The safety profile was consistent with previous studies of low-dose rhIL-6.
• The company is prioritizing the larger DPN market for Phase 2 development.
• The company has initiated a partnering process to move the asset forward towards commercialization.

Negatives

• One patient withdrew from the study due to severe fatigue.
• The SB211 CIPN development will be placed on hold to focus on DPN.

Risks

• The company needs to secure a partnership to move forward with the Phase 2 trial in DPN.
• The unblinded safety data is not yet available and is expected in the second half of 2024.
• The company is placing the CIPN development on hold, which may impact the timeline for that indication.

Future Outlook

The company plans to initiate a Phase 2 clinical trial in Diabetic Peripheral Neuropathy (DPN) after securing a potential partnership, leveraging the safety data from the Phase 1b trial of SON-080 in CIPN. The unblinded safety data from two dose levels of SON-080 compared to placebo are expected during the second half of 2024.

Management Comments

• Pankaj Mohan, Ph.D., Sonnet Founder and Chief Executive Officer, stated that the completion of the Phase 1b portion of SB211 is an important milestone for Sonnet in bringing a potentially groundbreaking treatment forward for peripheral neuropathies.
• Dr. Mohan also mentioned that the company has received greater potential partnering interest in the DPN indication.
• Richard Kenney, M.D., Sonnets Chief Medical Officer, noted that the use of SON-080 in CIPN was expected to provide a similar adverse event profile at low doses, based on previous studies of Interleukin-6 in cancer patients.

Industry Context

This announcement is relevant to the broader pharmaceutical industry, particularly in the development of treatments for peripheral neuropathies. The focus on DPN reflects the significant market opportunity in diabetes-related complications. The use of rhIL-6 is a novel approach to treating the underlying causes of peripheral neuropathy, rather than just masking the symptoms.

Comparison to Industry Standards

• The maximum tolerated dose of early versions of rhIL-6, such as Seronos atexakin alfa, was 10 g/kg three times a week (TIW), with significant side effects at doses over 2 g/kg TIW.
• Sonnet's SON-080 is being tested at lower doses, up to 1 g/kg TIW, with a focus on safety and tolerability.
• The company is leveraging the historical safety data of atexakin alfa in cancer patients to support the development of SON-080 in neurotherapy indications.
• The shift in focus to DPN is likely due to the larger market opportunity compared to CIPN, aligning with industry trends of prioritizing indications with higher commercial potential.

Stakeholder Impact

• Shareholders may view this as positive news, as it indicates progress in the development of SON-080.
• Patients with peripheral neuropathies may benefit from the potential development of a new treatment.
• The company's employees may be impacted by the shift in focus to DPN.

Next Steps

• The company will proceed with the Phase 2 clinical trial in DPN after securing a potential partnership.
• The unblinded safety data from two dose levels of SON-080 compared to placebo are expected in the second half of 2024.

Key Dates

Keywords

SON-080, rhIL-6, CIPN, DPN, clinical trial, Phase 2, safety, neuropathy, Data Safety Monitoring Board, immunotherapeutic