FDA Grants Rare Pediatric Disease Designation to Treatment for Ependymoma

The FDA has awarded a Rare Pediatric Disease Designation (RPD) to WP1066, a p-STAT3 inhibitor that treats patients with ependymoma, a rare type of tumor that develops in the brain or spinal cord.

Ependymoma forms in the ependymal cells of the brain and spinal cord, which line the passageways in which cerebrospinal fluid nourishes brain flows. The disease can occur at any age but occurs most frequently in young children.

WP1066, which appears to directly elicit tumor cell death and prompt the immune system to attack tumors, was previously granted 3 RPD designations in diffuse intrinsic pontine glioma, medulloblastoma, and atypical teratoid rhabdoid tumors.

“The FDA’s recognition of the high prevalence and unmet needs in the treatment landscape for ependymoma, especially in pediatric patients is a significant milestone as we continue to advance and expand the WP1066 development program,” said Walter Klemp, chairman and chief executive officer of Moleculin, in a press release. “We currently have orphan drug designation for WP1066 for the treatment of brain tumors, as well as RPD designation for 3 other pediatric indications, and believe that ependymoma represents another important rare indication.”

The novel drug is an immune/transcription modulator that can directly inhibit certain key oncogenic transcription factors, which include the activated form of STAT3 known as p-STAT3, which is considered a master regulator of tumor activity. The drug can also inhibit several other signaling proteins that have been linked to tumor development and stimulates a natural immune response and memory to fight tumor progression.

WP1066 has shown antitumor efficacy across a wide variety of tumor cell lines, indicating a survival benefit in several animal models. Further, WP1066 can enhance the antitumor effects of the immune system and its response to tumor activity. Research also suggests the agent may have a dual-action mechanism that allows for the treatment of an array of resistant tumors and can be paired in novel combinations for unresponsive tumors.

Subject to FDA approval of WP1066 for ependymoma, Moleculin Biotech, the drug developer, would be eligible for a voucher that may be redeemed to receive priority review for a subsequent marketing application for a different product candidate or that could be sold or transferred.

“We continue to be encouraged by the data WP1066 has demonstrated to date and believe it has potential to be an effective therapy for pediatric patients with ependymoma,” Klemp said in the release.