Ilex evaluates oral clofarabine in advanced solid tumours

Ilex Oncology has initiated a Phase I clinical trial to evaluate the safety and tolerability of oral clofarabine

The trial will be in adult patients with locally advanced or metastatic solid tumours who have either failed standard therapy or for whom no standard therapy exists. In addition, it will evaluate preliminary evidence of clofarabine's anti-tumour activity.

'Preclinical data suggests that clofarabine may be active in a range of solid cancers,' said Ilex ceo and president Jeff Buchalter. 'An oral formulation of clofarabine will provide greater flexibility in dosing and will further differentiate this drug.'

Phase I trial

This open-label, single-arm, dose-escalating Phase I study will enroll approximately 25 patients in the US. Oral clofarabine will be administered daily for five days. Treatment may be repeated every 28 days based on toxicity, up to a maximum of 12 cycles. Dose escalation will allow the identification of a maximum-tolerated dose and dose-limiting toxicity.

Clofarabine

Clofarabine is a next generation purine nucleoside antimetabolite. Nucleoside analogs are antimetabolites that affect DNA synthesis. Ilex obtained the right to develop clofarabine in the US and Canada from Bioenvision, which maintains its rights to develop clofarabine outside of those areas. In September, Ilex was granted a "fast-track" designation for clofarabine in refractory or relapsed pediatric acute lymphoblastic leukaemia (ALL). Designation as a fast track drug indicates that the FDA will facilitate the development and expedite the review of a new drug that is intended to treat a serious or life-threatening condition and that demonstrates the potential to address an unmet medical need. Clofarabine was previously granted orphan drug designation for the treatment of adult and pediatric ALL and acute myelogenous leukemia (AML) by the FDA. In the US, orphan drug status guarantees seven years of market exclusivity for the orphan drug indication following the FDA's marketing approval. Ilex has submitted the first part of a New Drug Application (NDA) with the FDA for clofarabine for the treatment of refractory or relapsed pediatric acute leukemia. It is anticipated that the remainder of the NDA will be submitted on a "rolling" basis and is expected to be completed in the first half of 2004