Prescient Therapeutics Ltd is set to present data from its Phase 1b study of PTX-100 in T-cell lymphomas (TCLs) at the 16th Annual T-Cell Lymphoma Forum in La Jolla, California, this weekend.
Prescient Therapeutics CEO James McDonnell said: “This is a very timely meeting as we move to initiate our phase 2a study of PTX-100 in patients with relapsed and refractory cutaneous T-cell lymphomas (CTCL) next month.
Key opinion leaders
“The forum is an excellent opportunity to engage global key opinion leaders in the field, including clinicians who will be conducting the study in their institutions.
“It will also be an excellent opportunity to consolidate relationships with potential partners for the further development of PTX-100.”
The specialist forum, attended by global experts in the field of T-cell lymphomas, will feature Prescient’s latest clinical and pharmacokinetic findings.
Data will include insights into the drug’s safety profile, efficacy, mechanism of action and pharmacokinetics.
The Phase 1b study enrolled 19 patients and tested PTX-100 at doses of 500, 1,000 and 2,000 mg/m².
The drug demonstrated a favourable safety profile, with an overall response rate of 42% among all evaluable TCL patients.
Six out of seven patients benefit
Among cutaneous T-cell lymphoma (CTCL) patients specifically, six out of seven evaluable participants derived clinical benefit.
Responders had a median progression-free survival exceeding 10 months, considerably beyond the typical 3.1 months observed with standard treatments such as vorinostat.
The Phase 1 study has now concluded, with one patient continuing to receive PTX-100 under compassionate access in Australia, having achieved a complete response.
Pharmacokinetic analyses showed PTX-100 is cleared efficiently from the body and does not accumulate, supporting its suitability for long-term use.
In vitro drug interaction studies indicated a low risk of interactions with other therapies, bolstering the drug’s clinical profile.
These results provide the rationale for advancing PTX-100 into a Phase 2a trial in patients with relapsed and refractory CTCL, which is scheduled to commence in April 2025.
The US Food and Drug Administration has granted Orphan Drug Designation to PTX-100 for all T-cell lymphomas.
PTX-100 is believed to be the only clinical-stage inhibitor of geranylgeranyl transferase-1 (GGT-1), a cancer growth enzyme that plays a role in oncogenic Ras signalling pathways.
It promotes apoptosis in cancer cells by blocking the activation of key pathways, including Rho, Rac and Ral.
Prescient Therapeutics is also progressing its CellPryme and OmniCAR cell therapy platforms, which are currently in preclinical development.