Not daunted by GB001’s blow-up in its phase II studies in asthma and chronic rhinosinusitis, Gossamer Bio has decided to push ahead with a phase III programme in the former indication – and to find a partner to pay for it. The Leda trial missed its primary endpoint of asthma worsening; on a conference call management attributed the lack of a dose-response to the prostaglandin D2 receptor antagonist achieving near-total receptor blockade at even the lowest dose, though of course this hardly explains the endpoint miss. Stronger responses in a subgroup found in a post-hoc analysis seem to be the trigger to push on, although executives failed to precisely characterise patients in the subgroup. Gossamer wants to begin a 12-month phase III trial with either the 20mg or 40mg dose. The sellside also found reasons for cheer: Leerink analysts noted that the exacerbation data “look good” and insisted Gossamer shares still look a “better buy than a sell”. Given the utter failure of other DP2 inhibitors in asthma all of this seems incredibly optimistic; even the 37% fall in the group’s share price is somewhat surprising, as GB001’s miss in Leda might have been expected.
|Data from phase IIb Leda trial of GB001 in moderate-to-severe eosinophilic asthma|
|Reduction in odds of asthma worsening vs placebo at 6mth (%)||33||32||35|
|Improvement in time to first asthma worsening vs placebo at 6mth (%)||28||23||30|
|Reduction in annualised severe exacerbation rate vs placebo at 6mth (%)||20||25||11|
|Adverse events (%)||66||66||70||68|
|Liver chemistry elevations leading to study drug discontinuation (%)||0.8||0.8||1.7||4.1|
|Source: Company press release.|