Clinical-stage biotech Celldex Therapeutics (CLDX 0.11%) was a standout on the stock market Monday. The company's share price closed a sturdy 13% higher on the day, thanks to freshly published data from a clinical trial of a key pipeline drug. This rise was far steeper than the 0.2% bump posted by the bellwether S&P 500 index.

Barzolvolimab did well in a phase 2 clinical trial

That morning, Celldex unveiled the results of a phase 2 study of barzolvolimab, a medication aimed at treating patients with moderate to severe chronic spontaneous urticaria (CSU) refractory to antihistamines.

The biotech reported that barzolvolimab achieved its primary efficacy endpoint in treating this form of urticaria (more commonly known as hives). It also achieved a statistically significant mean change from baseline to week 12 of the 208-participant trial when compared to a placebo.

Additionally, the drug was generally well tolerated in the study, and showed a favorable safety profile. The bulk of adverse events were mild to moderate in terms of severity.

Celldex continues to place high hopes on its pipeline drug. It quoted CEO Anthony Marucci as saying that the latest results "further establish barzolvolimab as a potential transformative treatment option for patients suffering with CSU. These data reinforce barzolvolimab's unique mechanism targeting a key underlying pathway of the disease."

Continued development

So Celldex will continue pushing along its development. Marucci added that the company's goal is to put the drug though its paces in registrational trials.

Although it's a "so far, so good" situation for the biotech and barzolvolimab, we should always bear firmly in mind that -- like stocks -- success in early-to-middle testing phases of a medication is no guarantee of future success or, importantly, authorization/approval from regulators. Still, the biotech's news was very encouraging for believers in its progress.