Prescient Therapeutics Limited provided an update on the PTX-100 Phase 1b expansion cohort in relapsed and refractory T cell lymphomas (TCL). The study is being led by globally renowned haematologist, Professor H. Miles Prince at Epworth Hospital in Melbourne, Australia. PTX- 100 continues to exhibit an excellent safety profile at the highest dose of 2000 mg/m2.

Moreover, PTX-100 continues to show encouraging clinical activity in a difficult to treat patient population, including a striking response in a patient with refractory cutaneous TCL (CTCL). The expansion cohort has targeted 8-12 patients. A total of 8 patients have been screened and 7 patients have been dosed with PTX-100 in the expansion cohort so far: 4 with peripheral TCL (PTCL) and 3 with CTCL.

Patients had received a median of 4 prior lines of therapy and up to 6 prior lines of therapy. PTX-100 was administered at 2,000 mg/m2. Four patients remain on therapy and additional patients are being recruited.

PTX-100 continues to exhibit an excellent safety profile on the study. There have been very few adverse events in the expansion cohort so far, and no serious adverse events related to PTX-100. 2 PTCL patients that had commenced therapy withdrew from the study for reasons unrelated to the trial.

Another PTCL patient passed away due to reasons not associated with the study, as frequently occurs in studies of advanced malignancies. In each of these cases, subjects were not on the study long enough to observe responses, however, relevant pharmacokinetic and safety data were still collected, which are to the primary objectives of the study. Although the primary goal of the expansion cohort is to evaluate safety, PTX-100 continues to exhibit encouraging clinical activity in the difficult-to-treat patient population.

An update of observed responses is summarised below: Patient 121-003 (previously reported in dose escalation component of the study) with aggressive PTCL that had failed five prior treatments, had a partial response that endured for over 32 months before the disease progressed. Patient 121-010 with CTCL that had failed 4 prior lines of therapy experienced a very good partial response (VGPR), which is almost a complete response, that has endured for 6 months so far. This patient remains on therapy.

Another 2 patients with CTCL that failed three prior therapies have experienced stable disease that have endured for 3-4 months so far and remain on therapy. CTCL patient that had failed 4 prior therapies. Patient had VGPR on PTX-100 and is still on treatment.