IMX-110 is currently in a Phase 1b/2a clinical trial.
The FDA grants the RPD status for serious and life-threatening diseases that primarily affect children under 18 years old; and impact fewer than 200,000 people in the US.
Rhabdomyosarcoma is a high-grade, malignant neoplasm, the most common soft tissue sarcoma in pediatric and adolescent populations and which rarely occurs in adults. The prevalence of rhabdomyosarcoma in the country is approximately 20,000 children of all ages: and a five-year survival rate ranges from 20% to 30% for children in the high-risk group where cancer spreads widely in the body.
IMX-110 is ImmixBio’s lead candidate and the first clinical-stage product coming from its SMARxT Tissue-Specific Platform, which produces Tissue-Specific Therapeutics that accumulate at intended therapeutic sites at three to five times the rate of conventional medicines, according to the company.
The California-headquartered biotech recently shared clinical data across multiple soft tissue sarcoma subtypes in several heavily pretreated patients demonstrating median progression-free survival (PFS) of four months with zero drug-related severe adverse events and zero dose interruptions due to toxicity.
The Rare Pediatric Disease Designation qualifies Immix for fast track review.
If a New Drug Application for IMX-110 is approved, ImmixBio may be eligible to receive a Priority Review Voucher (PRV) from the FDA, which can be redeemed to obtain priority review for any subsequent marketing application, or may be sold or transferred.
“We are pleased by FDA’s acknowledgment of the urgent need for a safe and effective treatment for children with this devastating disease,” said ImmixBio CEO Ilya Rachman, M.D., 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.”
The FDA has already granted orphan drug designation (ODD) to IMX-110 for the treatment of soft tissue sarcoma.
Meanwhile, ImmixBio's collaborations with BeiGene and Novartis are also investigating the therapy for solid tumors.