Jasper shares surge after positive early trial for chronic hives drug

Jasper Therapeutics has demonstrated promising results with its anti-c-KIT antibody, briquilimab, in a Phase 1b/2a clinical trial involving patients with certain challenging skin conditions, leading to a significant increase in the company's stock on Monday. The SPOTLIGHT study, focusing on individuals with cold urticaria or symptomatic dermographism who do not respond to antihistamines, reported that fourteen out of fifteen participants showed a positive clinical response to briquilimab during the six-week initial analysis period.

Cold urticaria results from exposure to cold temperatures, while symptomatic dermographism occurs due to skin rubbing or scratching, both causing hives and swelling. This new treatment option could be significant for patients struggling with these conditions.

On Monday, Jasper Therapeutics' shares surged by up to 20% following the announcement. Among the twelve participants who received a higher 120 mg dose of briquilimab, ten exhibited a complete response, and one had a partial response. William Blair analysts noted that the data indicated clear activity for briquilimab, showing a rapid onset of action both in response rate and in reducing serum tryptase levels.

However, it was observed that the complete responses to briquilimab were temporary, lasting only around four weeks before the number of responders decreased from ten to six. This contrasts with Celldex Therapeutics' anti-KIT antibody, barzolvolimab, which, at a 1.5 mg/kg dose, maintained responses for six weeks in a similar patient group. Despite this, nearly half of Celldex’s study participants experienced hair color changes, an adverse effect not observed in Jasper’s study.

In the SPOTLIGHT study, briquilimab was well-tolerated, with no serious or grade 3 or higher adverse events reported. Additionally, there were no observed side effects related to skin or hair color changes.

Jasper Therapeutics has received regulatory approval to introduce a 180 mg dose cohort to the SPOTLIGHT study, with comprehensive results anticipated in the first half of the next year.

In another ongoing investigation, the BEACON trial, Jasper's briquilimab is being evaluated in patients with chronic spontaneous urticaria who continue to experience symptoms despite treatment with Novartis and Genentech’s Xolair or are intolerant to it. Initial findings from this study are expected in January.