FDA Grants Rare Pediatric Disease Designation to Novel Treatment for Rhabdomyosarcoma

The FDA has granted rare pediatric disease designation to IMX-110 for the treatment of rhabdomyosarcoma, a life-threatening caner found in children. This designation makes IMX-110 eligible for a fast track designation and a priority review designation in the future, according to a press release by Immix Biopharma, Inc, in a press release.¹

IMX-110 is a poly-kinase inhibitor designed to treat soft tissue sarcoma as a single-agent and to treat solid tumors when administered in combination with the monoclonal antibody tislelizumab (BGB-A317). IMX-110 produces Tissue-Specific Therapeutics that collect at intended therapeutic sites at 3 to 5 times the rate of standard drugs. The agent already has an orphan drug designation granted by the FDA for the treatment of soft tissue sarcoma.

“We are pleased by FDA’s acknowledgment of the urgent need for a safe and effective treatment for children with this devastating disease,” stated ImmixBio’s Chief Executive Officer Ilya Rachman, MD, PhD. “We are encouraged by our phase 1b/2a clinical data in soft tissue sarcoma. IMX-110 is a tissue-specific therapeutic that simultaneously attacks all 3 components of the tumor micro-environment, severing the critical lifelines between the tumor and its metabolic and structural support. We believe our SMARxT platform generating Tissue-Specific Therapeutics represents a distinct alternative to the traditional ‘single target, single mutation’ development model.”

A phase 1b/2a clinical trial of IMX-110 in patients with advanced solid tumors is underway to further investigate its safety, tolerability, and pharmacokinetics. The study will enroll approximately 70 patients who will receive IMX-110 monotherapy. The coprimary end points being explored include the number of patients with treatment-related adverse events, the maximum-tolerated dose of IMX-110, and the recommended phase 2 dose of IMX-110.²

The secondary end points of the study are plasma concentration of IMX-110, response rate, progression-free survival, overall survival, and duration of response. Pharmacokinetic activity will be evaluated as an additional outcome.

To be eligible for the study, patients aged 18 years or older with a confirmed diagnosis of a solid tumor, an ECOG performance status of 0-2, a life expectancy of 3 months, adequate cardiac function, and adequate laboratory values at baseline. Female patients must have a negative pregnancy test and both males and females must agree to use contraception during the study.

The study is actively recruiting patients at 2 sites in California as well as in Australia.

^References:

^{1. U.S. Food and Drug Administration approves Immix Biopharma rare pediatric disease designation for IMX-110 as a treatment for life-threatening pediatric cancer in children. News release. January 3, 2021. Accessed January 3, 2021. https://bit.ly/32X0pNQ}

^{2. IMX-110 in patients with advanced solid tumors. Clinicaltrials.gov. Accessed January 3, 2021. https://bit.ly/3JAmaE1}