HTL-001 is a small (18-amino acid) peptide with attractive pharmaceutical properties. Together with its predecessor HXR9, it has proved to be effective against numerous cell lines, tumour samples, and human tumours . A comprehensive preclinical toxicology package, approved by the MHRA, in two animal species has been completed with no unexpected toxicities at doses well within the range expected to be administered to humans.
A Phase I first-in-man study involving around 20 patients treated with intravenous HTL-001 is planned for 2019. These patients will have progressed despite conventional treatment, and the study will be designed to determine that treatment with HTL-001 is safe, non-toxic and has anticancer effects.
As noted above, HTL-002 is a small molecule version of HTL-001 and is the product of several years of research into the active component of this peptide and subsequent screening of library and novel product candidates. HTL-002 is a novel compound and is in the early stages of development, albeit with a considerable foundation in the form of knowledge and experience of the peptide precursor. The current lead compound has an attractive profile and the results of initial in-vivo studies are encouraging. HTL-002 is the subject of comprehensive composition of matter patents filed in 2016.
For any new cancer therapy, development requires a means of predicting and monitoring the efficacy of treatment. This in turn requires biomarkers, which include surrogate indicators of disease that can be measured and monitored. Short of frequent biopsies, developing biomarkers is not necessarily straightforward for all therapies.
A number of biomarkers have been developed for measuring the response of tumours to HOX/PBX inhibition, as well as predicting tumour sensitivity. These will be further evaluated in clinical trials of HTL-001 and HTL-002.