Moleculin Rises on Promising Pediatric Brain Tumor Drug Data
Phase 1 trial of WP1066 shows positive safety and early anti-tumor signals in children with highly aggressive, recurrent brain cancers where few treatments exist.
Shares of Moleculin Biotech Inc. (NASDAQ: MBRX), a clinical-stage pharmaceutical company, climbed Tuesday after it announced positive results from a Phase 1 clinical trial of its drug candidate, WP1066, for the treatment of recurrent, malignant brain tumors in children.
The Houston-based company, which has a market capitalization of approximately $22.5 million, saw its stock price rise to $4.69 in afternoon trading. The promising, albeit early-stage, data represents a significant milestone for the firm and offers a glimmer of hope for a patient population with devastatingly few options.
The physician-sponsored Phase 1 trial evaluated WP1066 in children with some of the most aggressive and difficult-to-treat cancers, including diffuse intrinsic pontine glioma (DIPG), medulloblastoma, and ependymoma. According to the company's announcement, the study found that WP1066 was safe and well-tolerated, with no significant toxicity observed. Crucially, it also showed early signs of clinical activity.
Researchers noted that the drug induced anti-tumor immune responses and, significantly, led to a partial tumor response in one patient with DIPG—a universally fatal brain cancer. "The results of this first-in-child trial show some encouraging signals of activity in a highly aggressive chemotherapy resistant brain cancer," stated Dr. Tobey MacDonald, Professor of Pediatrics and Director of the Pediatric Neuro-Oncology Program at Emory University, who led the trial.
The significance of these findings is magnified by the dire prognosis for these diseases. Recurrent DIPG, for example, has a median overall survival of just 8 to 11 months, and there is currently no cure or effective standard therapy upon recurrence. The tumor's location in the brainstem makes it inoperable, and the blood-brain barrier poses a major challenge for drug delivery, rendering most chemotherapies ineffective.
Moleculin's WP1066 is designed to inhibit the STAT3 protein, a key signaling molecule often implicated in tumor growth and immune suppression. The trial's findings suggest the drug successfully suppressed STAT3 activity, potentially reactivating the patient's immune system to fight the cancer.
Walter Klemp, Moleculin’s Chairman and CEO, framed the results as an important validation of the drug's mechanism. “These early data show that WP1066 has the ability to activate meaningful anti-tumor immune responses, an important proof of mechanism in a patient population with extremely limited treatment options,” Klemp said in a statement. “These findings reinforce the potential of WP1066 as a novel immunomodulatory approach for some of the most difficult-to-treat pediatric brain cancers.”
The development path for WP1066 is supported by the U.S. Food and Drug Administration, which has previously granted it Orphan Drug and Rare Pediatric Disease designations for several of these indications. These designations provide incentives for development, and a potential approval could lead to a Priority Review Voucher, a valuable asset that can be used to expedite the review of another drug or be sold to another company.
For a small-cap biotech like Moleculin, positive data in a high-unmet-need area like pediatric oncology can be a major value inflection point. While the trial was small, with just 10 children, the safety and early efficacy signals are sufficient to warrant further investigation, with researchers suggesting the results support advancing to a Phase 2 trial.
Despite the positive news, the stock remains well below its 52-week high of $69.50, reflecting the inherent risks of early-stage drug development. However, with three analysts covering the stock holding an average price target of $6.67, the successful Phase 1 data provides a fundamental basis for renewed investor interest as the company charts the next clinical steps for WP1066.