Jasper Reports Positive Mid-Stage Results for Urticaria Drug, Targets Blockbusters

Jasper Therapeutics has announced promising results for its investigational antibody briquilimab in the treatment of chronic inducible urticaria, showing potential to compete with established treatments like Novartis and Genentech’s Xolair, and Sanofi and Regeneron’s Dupixent.

The top-line results from its Phase Ib/II SPOTLIGHT study revealed significant efficacy in patients. During the initial six weeks of treatment, 14 out of 15 patients demonstrated a clinical response to briquilimab in a provocation test. Specifically, among those who received a 120-mg dose, 83% achieved a complete response. This group experienced an improvement in the critical temperature threshold to at least 4°C for cold urticaria patients, and improved FricTest dermographometer scores to zero for those with symptomatic dermographism. One patient in this group had a partial response as their best outcome.

In the cohort that received a 40-mg dose, one patient reached a complete response, while the remaining two had partial responses. The study also showed significant reductions in serum tryptase levels as early as one week after treatment with the 120-mg dose. By six weeks, the mean tryptase levels had dropped by 31% from baseline, with one patient noting a 66% reduction by the second week.

Safety data from the SPOTLIGHT study indicated that briquilimab was generally well-tolerated, without any severe or grade 3 adverse events. Importantly, there were no reports of hypersensitivity, anemia, or changes in hair or skin color.

Jasper Therapeutics' CEO, Ronald Martell, expressed enthusiasm about these findings, stating that the data highlight briquilimab's ability to deliver robust and durable clinical benefits rapidly, coupled with a potentially favorable safety profile. Analyst Matt Phipps from William Blair also commented on the results, noting the strong initial efficacy of a single 120-mg subcutaneous dose of briquilimab. He pointed out that there are still questions regarding the durability of the treatment’s effects. However, the current data suggest that at a minimum, briquilimab could be administered every four weeks. He hypothesized that higher doses, such as 180 mg or 240 mg, might offer even greater durability and potentially less frequent dosing, deeming this an important de-risking event for Jasper.

Briquilimab operates as an investigational aglycosylated monoclonal antibody targeting the stem cell factor. It disrupts its binding to the CD117 receptor, present on several healthy cells including mast cells. This mechanism allows briquilimab to block vital cell survival signals, leading to the depletion of mast cells and suppression of the inflammatory response in various diseases.

With the positive readout from Monday, Jasper Therapeutics is set to challenge significant players in the inflammatory disease market. Xolair, an anti-IgE antibody first approved in 2003, is used for asthma, nasal polyps, and chronic idiopathic urticaria. It generated $1.46 billion in sales last year, marking a 9% increase year-over-year.

Dupixent, approved in 2017, treats atopic dermatitis, asthma, eosinophilic esophagitis, and chronic rhinosinusitis with nasal polyps. Recently, it received a label expansion to include chronic obstructive pulmonary disease, expected to further boost its sales. Last year, Dupixent generated around $11.6 billion.