Istesso backer sees silver lining in failed arthritis trial
X-ray of the hand in rheumatoid arthritis
Shares in the UK's IP Group slid today after it revealed that an arthritis drug in development at one of its portfolio companies, Istesso, had failed a phase 2b trial.
The early-stage investor in life sciences companies said Istesso's mitochondrial complex 1 inhibitor leramistat (MBS2320) was unable to meet its primary objective of improving tender and swollen joints in patients with moderate-to-severe rheumatoid arthritis (RA) unresponsive to methotrexate, measured using the ACR20 scale, compared to placebo.
The announcement sparked a 5% fall in IP Group's shares, despite its assertions that the study, in fact, reinforces the potential of leramistat in RA.
It is drawing comfort from secondary measures in the 12-week, phase 2b IST-06 trial, particularly a reduction in bone erosion in the joints compared to placebo, which it said provided evidence backing up the drug's proposed mechanism of action. Reported adverse events were also mild and resolved without intervention.
According to the company, leramistat is designed to augment the body’s inherent repair response to repair and restore damaged tissue and build resilience to further damage – without suppressing the immune system. The reduction in bone erosion was accompanied by improvements in disability and fatigue, according to the top-line data.
The study results "support further evaluation of [leramistat's] potential to promote adaptive tissue repair in combination with existing disease-modifying anti-rheumatic drugs (DMARDs) in RA, as well as in other chronic conditions," it added.
Istesso plans to run additional phase 2 trials of leramistat and has the funding in place to complete those studies, according to IP Group, which holds a majority 56.5% stake in the London-based biotech.
Other potential indications for the drug include chronic conditions associated with autoimmunity, fibrosis and bone loss, with studies already underway in idiopathic pulmonary fibrosis (IPF).
"We are encouraged that these results are consistent with leramistat’s unique mechanism of action, which supports and augments tissue repair," commented IP Group chief executive Greg Smith.
"In addition, the impact on disability and fatigue, from which a large proportion of RA patients continue to suffer despite the widespread availability of current medications, is also highly promising," he added.
"Based on these data, we continue to believe in the market opportunity for leramistat to improve patients’ health and deliver significant value for shareholders."
Any new approach to the treatment for RA would be welcome because while new therapies like JAK inhibitors have made it possible for many patients to achieve long-term remission from symptoms, there is still a proportion in whom the disease is persistent and difficult to treat. Around 17.6 million people live with RA globally.
