Monopar Therapeutics is moving on from a treatment for chemotherapy side effects after a disappointing interim analysis from a phase 2 trial left the company empty-handed.
The Illinois biotech said that a treatment for severe oral mucositis, a side effect of chemotherapy, has been discontinued after not meeting the pre-specified efficacy endpoints in a phase 2/3 trial at the interim analysis. The news Tuesday sent the company’s shares down more than 50% shortly after the market opened from $2.98 per share to $1.45.
Monopar reported that Validive did not produce at least a 15% difference in mucositis prevention compared to placebo. The analysis was conducted on 50% of the patients that were expected to be enrolled in the trial. The therapy was aimed at patients with oropharyngeal cancer that were treated with chemotherapy.
CEO Chandler Robinson, M.D., said in a statement that while the company was disappointed, resources would be redirected toward its radiopharmaceutical programs and phase 1 asset camsirubicin. The latter is indicated for advanced soft tissue sarcoma. Monopar says it has enough cash to last beyond the first quarter of 2024.
Camsirubicin is an analog version of the chemotherapy doxorubicin, meant to capitalize on the efficacy of the treatment while mitigating toxicity at higher dose levels. Monopar is in the process of confirming this hypothesis through a phase 1b dose-escalating study that’s still enrolling. Monopar reported last week in its fourth-quarter earnings report that a fifth dosing cohort is being enrolled at a level 2.5-times the highest dose level assessed in prior studies. The company says that so far, no cardiotoxicity events have been reported among treated patients, defined by left-ventricular ejection fraction, and 75% of treated patients have had no hair loss.
An imaging agent for the radiopharmaceutical program is slated to be ready for a clinical trial before the end of the year.