Acorda shares crash after deaths in Parkinson's trials


Shares in US biotech Acorda have crashed after five deaths caused by infections in patients treated with its late-stage Parkinson’s drug, tozadenant, prompting the firm to pause trial recruitment and increase patient surveillance.

Based in New York state, Acorda said the action was in response to cases of agranuloctytosis – the absence of white blood cells that fight infection.

There is a dearth of new drugs for Parkinson’s disease, a neurogenerative condition that causes a deficiency in the neurotransmitter dopamine, and the news from Acorda will be a major blow to patients and doctors looking for new and more effective therapies.

Existing therapies can only help treat symptoms and reduce 'off' episodes when patients suffer tremors and have difficulty walking.

When Newron finally gained approval for its Xadago (safinamide) earlier this year, after numerous delays, it was the first new drug approved in a decade.

The bad news from Acorda sent its shares down almost 40% on the NASDAQ stock exchange, prompting a halt in trading, as investors feared this could be the end for tozadenant.

Acorda’s phase 3 development programme includes an ongoing pivotal efficacy and safety study and two long-term safety studies.

Patient enrolment on the last two trials has been paused and the company has stepped up monitoring of white blood cell counts on those still being treated.

In trials, 890 patients have been exposed to tozadenant and 234 have been on placebo. This corresponds to approximately 300 patient years of tozadenant exposure and 75 patient-years of placebo.

But in patients treated with tozadenant there have been seven cases of sepsis, five of which were fatal.

Four of the sepsis cases were associated with agranulocytosis, two had no white blood cell counts available at the time of the event, and one had a high white blood cell count.

Acorda CEO Ron Cohen

President and CEO Ron Cohen said: “We have taken these steps in the best interests of the safety of patients in the tozadenant studies, which is our top priority.”

Acorda will get further feedback from the FDA and the trial’s independent safety monitoring board and report efficacy and safety results of the double-blind phase 3 study in the first quarter of 2018.

Tozadenant is an oral adenosine A2a receptor antagonist currently in phase 3 development as an adjunctive treatment to levodopa in Parkinson’s disease patients to reduce off time.

Acorda hopes A2a receptor antagonists could be the first new class of drug approved in the US for improvement of motor symptoms in Parkinson’s disease in over 20 years.