CytRx Corporation (NASDAQ:CYTR), a biopharmaceutical company, is permitted to re-enter the clinic with its orally administered molecular chaperone drug candidate arimoclomol as a therapeutic treatment for amyotrophic lateral sclerosis (ALS or Lou Gehrig’s disease), following the U.S. Food and Drug Administration’s (FDA) acceptance of a revised clinical trial protocol.
“We are delighted with the FDA’s decision to approve a protocol that provides a safe and efficient avenue to ascend arimoclomol dosing to the target dosage level of 400 mg three times daily, which we believe will prove most effective in treating ALS patients,” said CytRx President and CEO Steven A. Kriegsman. “Arimoclomol’s underlying molecular chaperone amplification method of action has shown promising clinical and preclinical study results in inhibiting the progression of ALS, a debilitating disease that currently lacks effective therapeutic treatment. We believe that this drug candidate has the potential to be a breakthrough drug with application in a number of other neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease and Huntington’s disease, and as a treatment for stroke recovery and neuropathy. Recent independent findings also indicate that molecular chaperone technology represents a significant strategy in the future design of anti-aging pharmaceuticals.
“We have attracted significant interest from several pharmaceutical companies as potential partners to advance development of our molecular chaperone programs, and we view clearance to resume arimoclomol clinical testing as a key step in moving these negotiations forward. Given the significant opportunity arimoclomol presents in ALS, we are prepared to resume the clinical trial in parallel with our discussions,” he added.
CytRx Chief Medical Officer Daniel J. Levitt, M.D., Ph.D., said, “The revised protocol allows for a safety assessment and a preliminary efficacy evaluation in ALS patients treated with arimoclomol at levels up to four times the dose administered in our prior Phase IIa clinical trial and open label extension study. Arimoclomol will be administered in combination with riluzole (Rilutek®), the only currently FDA-approved treatment for ALS, which typically prolongs life by approximately two months. We currently estimate that data from this trial, should all tiers be completed, will be available approximately 18 months from the time the trial starts.”
The clinical trial protocol accepted by the FDA is a tiered, placebo-controlled, double-blind ascending dose study. The study is designed to test progressive groups each with between 20 and 30 ALS patients over a three-month treatment period. Fifteen patients will receive a combination of arimoclomol at various dose levels and riluzole at a fixed dose of 50 mg twice daily, with between five and 15 ALS patients receiving placebo and riluzole at the same fixed dose. The first group will receive arimoclomol 100 mg capsules three times daily. Every four weeks, another group of ALS patients will begin three-month testing with six patients receiving arimoclomol dosing three times daily at a 75 mg per dose increase from the prior group. The maximum dose in the protocol allows for testing arimoclomol at 400 mg three times daily. An independent safety monitoring board will review safety results prior to initiating each consecutive increase in dosage level.
The trial’s endpoints include a preliminary evaluation of efficacy using two widely accepted surrogate markers, the revised ALS Functional Rating Scale (ALSFRS-R), which is used to determine patient’s capacity and independence in 13 functional activities, and Vital Capacity (VC), an assessment of lung capacity. The trial is powered to monitor only extreme responses in these two categories.
The FDA has granted Fast Track designation and Orphan Drug status to arimoclomol for the treatment of ALS. Arimoclomol has also been granted orphan medicinal product status for the treatment of ALS from the European Medicines Agency.