Heidelberg Pharma’s Partner Telix Receives FDA Complete Response Letter for TLX250-CDx
Thursday, August 28, 2025
Heidelberg Pharma announced that its licensing partner, Telix Pharmaceuticals, has received a Complete Response Letter (CRL) from the US Food and Drug Administration (FDA) for its Biologics License Application (BLA) for TLX250-CDx.
The application was submitted at the end of December 2024 and was accepted for Priority Review in February 2025, with a review deadline of 27 August 2025. However, the FDA has highlighted deficiencies in the Chemistry, Manufacturing and Controls (CMC) package. The agency has requested further data to confirm comparability between the material used in the Phase 3 ZIRCON study and the commercial-scale manufacturing process. In addition, deficiencies were noted at two external manufacturing and supply chain partners, which must be addressed before resubmission.
Telix expects these issues can be resolved and plans to begin remediation immediately. Revised timelines for resubmission will be announced once available.
Under its agreement with Telix, Heidelberg Pharma is entitled to milestone payments and royalties if TLX250-CDx gains regulatory approval. The company had also sold part of its future royalty income to HealthCare Royalty (HCRx), making it eligible to receive USD 70 million upon FDA approval. As approval has not been granted, this condition remains unmet, and Heidelberg Pharma’s cash position is expected to last until the first quarter of 2026.
The company’s Executive and Supervisory Boards are reviewing alternative financing options alongside potential cost-saving measures.
Source: heidelberg-pharma.com
