Treadwell Therapeutics said that the US Food and Drug Administration (FDA) has accepted its Investigational New Drug (IND) application to evaluate its CFI-402411 for solid tumours.

CFI-402411 is an oral haematopoietic progenitor kinase 1 (HPK1) inhibitor used as a monotherapy or in combination with PD1 pathway blockade for patients with solid tumours.

In addition to the of IND acceptance, Treadwell has also received a no objection letter (NOL) from Health Canada, for Clinical Trial Application (CTA) for CFI-402411 in solid tumours.

Treadwell co-chief executive officer Shane Burgess said: “HPK1 represents a novel, orally targettable node of therapeutic intervention in the immune-oncology space.

“As a pleiotropic negative regulator of immune cell activation, inhibiting HPK1 may result in more potent anti-tumour responses in the treatment of cancer, simultaneously acting on multiple immune cell subsets to prevent tumour evasion.

“Therefore, we are excited to have received the FDA’s IND clearance to begin clinical trials for our first-in-class, highly-potent, oral HPK1 inhibitor.”

Treadwell will evaluate safety, tolerability, pharmacokinetics, pharmacodynamics and efficacy of CFI-402411

With the regulatory acceptance, Treadwell is planning to begin a Phase 1/2 clinical trial of CFI-402411, in the third quarter of 2020.

CFI-402411 is a potential HPK1 inhibitor which has demonstrated immune-activating effects through effector cells, and cytotoxic effects on specific subtypes of AML mouse models, in preclinical studies.

Immune-activating effects include the alleviation of inhibition of T cell receptors (TCR), disruption of abnormal cytokine expression, alteration of the tumour immunosuppressive environment.

The company has designed the clinical trial to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics and efficacy of CFI-402411, and to determine optimal dosing as a monotherapy and in combination with PD1 pathway inhibitors.

Treadwell Therapeutics is a clinical-stage oncology company engaged in developing advanced small molecules to address unmet needs in patients with cancer.

Treadwell chief scientific officer and co-founder Mark Bray said: “Our inhibitor program is the culmination of over two decades of pioneering work by Treadwell Founders and collaborators in HPK1 biology and immune regulation.

“Preclinical studies have demonstrated CFI-402411’s promise as a potential monotherapy and in combination with existing checkpoint inhibitors across both solid and haematological cancers, and we look forward to our Phase 1/2 trial later this year.”