Heidelberg Pharma AG, a clinical-stage developer of innovative Antibody Drug Conjugates (ADCs), announced today that new clinical data from its ongoing Phase I/IIa study of lead candidate HDP-101 will be presented at the 16th Annual World ADC Congress in San Diego, California. The data, to be shared on November 5, 2025, show objective responses and promising anti-tumor activity in several patients across multiple cohorts, reinforcing the therapeutic potential and safety profile of HDP-101 in relapsed or refractory multiple myeloma.
HDP-101 (INN: pamlectabart tismanitin) is an anti-BCMA antibody-drug conjugate being investigated for the treatment of relapsed or refractory multiple myeloma, a bone marrow cancer with high unmet medical need. The Phase I portion of the study is a dose-escalation trial designed to determine the optimal and safe dose level in preparation for Phase II clinical evaluation. Professor Andreas Pahl, Chief Executive Officer of Heidelberg Pharma, will present an update from patient cohort 8, including efficacy data from the open-label, multicenter study.
Following the congress, Heidelberg Pharma will host an R&D webinar on November 11, 2025, at 5:00 pm CET (11:00 am EST; 08:00 am PST) for investors, analysts, and media. The webinar will feature presentations by the Heidelberg Pharma management team alongside Key Opinion Leader Professor Marc-Steffen Raab, Head of the Myeloma Center at the University Hospital Heidelberg and clinical investigator of the study. Participants may submit questions in advance or ask them live during the event. Registration is available via Zoom.
Heidelberg Pharma is the first company to use Amanitin, a compound from the green death cap mushroom, in cancer therapy. The toxin's biological mechanism of action represents a new therapeutic modality and is utilized in the company's Amanitin-based ADC technology, known as ATAC technology. The lead candidate HDP-101 is a BCMA ATAC in clinical development for multiple myeloma. A second ATAC candidate, HDP-102, recently started clinical development in Non-Hodgkin Lymphoma but is currently on temporary hold. HDP-103 against metastatic castration-resistant prostate cancer and HDP-104 targeting gastrointestinal tumors such as colorectal cancer have completed preclinical development. Heidelberg Pharma is open for partnering.
The company is based in Ladenburg, Germany, and is listed on the Frankfurt Stock Exchange (ISIN DE000A11QVV0 / WKN A11QVV / Symbol HPHA). More information is available at www.heidelberg-pharma.com. ATAC is a registered trademark of Heidelberg Pharma Research GmbH.
