Connect Biopharma reported a statistically significant improvement in lung function in its Phase 2 Seabreeze STAT asthma trial, while a 66% reduction in treatment failures did not reach statistical significance.
Key Investor Takeaways
- Connect Biopharma (NASDAQ:CNTB) said rademikibart produced a statistically significant 130 mL placebo-adjusted improvement in post-bronchodilator FEV1 at Day 7, with a p-value of 0.023.
- The Phase 2 trial showed an approximately 66% reduction in treatment failure over 28 days, but the primary endpoint was not statistically significant at p=0.153.
- Emergency department or unscheduled medical visits for worsening asthma symptoms were reduced by 50% compared with placebo.
- No new safety signals were observed, with adverse-event incidence described as low and the safety profile comparable to placebo.
- Connect plans to use the results to inform a Phase 3 program, with Phase 2 COPD data expected later this month before discussions with the FDA.
Why CNTB Stock Is in Focus
Connect Biopharma reported preliminary topline data from its 160-patient Phase 2 Seabreeze STAT Asthma study evaluating rademikibart as an add-on to standard care for acute asthma exacerbations in patients with type 2 inflammation.
The randomized trial assigned 79 patients to a single 600 mg subcutaneous dose of rademikibart and 81 to placebo.
At Day 7, post-bronchodilator FEV1 increased by 250 mL from baseline in the rademikibart group versus 120 mL with placebo. The resulting 130 mL placebo-adjusted improvement was statistically significant at p=0.023.
The study’s primary endpoint, however, did not achieve statistical significance. Rademikibart reduced treatment failures by approximately 66% over 28 days compared with placebo, but the result produced a p-value of 0.153. Connect attributed the miss to an overall treatment failure rate that was lower than projected.
Treatment failure included events such as hospitalization, emergency department or unscheduled medical visits for worsening asthma, treatment intensification or death.
Why This Matters for Investors
The Phase 2 results present investors with a mixed but potentially consequential clinical readout.
The primary treatment-failure endpoint missed statistical significance, which limits the conclusions that can be drawn from the reported 66% reduction. At the same time, rademikibart achieved statistical significance on the key secondary FEV1 endpoint, providing evidence of improved lung function one week after treatment.
That FEV1 result is particularly relevant to Connect’s development strategy because the company said the measure is also its proposed primary endpoint for Phase 3. The Phase 2 data therefore may influence how Connect structures a registrational program rather than ending development based on the missed primary endpoint.
Safety provides another component of the readout. No adverse events resulted in study discontinuation, and there was one serious adverse event in the rademikibart arm compared with three in the placebo group. Connect reported no new safety signals.
The next question for investors is whether regulators agree with the company’s proposed path forward. Connect intends to seek FDA alignment on a Phase 3 registrational program covering acute exacerbations of asthma and COPD after receiving data from its separate COPD study.
What to Watch Next
The most immediate catalyst is topline data from the Phase 2 Seabreeze STAT COPD trial, which Connect expects to report later in September.
Attention will then shift to FDA discussions over the proposed Phase 3 program, including whether the agency supports using post-bronchodilator FEV1 as the primary endpoint.
Investors can also watch for additional details from the asthma dataset that clarify the treatment-failure result, the lower-than-expected event rate and how those findings affect Phase 3 trial design and powering.