An antibody-drug conjugate, made with a toxic mushroom rather than chemotherapy, has shown promising results in a Phase 1/2a trial in patients with multiple myeloma. The drug, HDP-101 (pamlectabart tismanitin), is being developed by Heidelberg Pharma AG of Germany. In October it received a ‘fast track’ designation from the US Food and Drug Administration for its potential as a treatment for severely ill and heavily pretreated patients.
Multiple myeloma cells are abnormal plasma cells that build up in the bone marrow and form tumours in many bones of the body. The disease has a global incidence of 2.1 cases per 100,000 people. The most recent patent cohort consisted of seven patients of whom four showed biological activity, with one partial response, one very good partial response, and two stringent complete remissions, according to the company.
“Observing two stringent complete remissions is an encouraging validation of our therapeutic approach,” András Strassz, the company’s chief medical officer, said in a prepared statement. The company is now preparing to treat a potentially final cohort with a higher dose. Heidelberg is the first company to use the toxic compound amanitin from a mushroom in an ADC.
Copyright 2025 Evernow Publishing Ltd