Lou Gehrig’s disease is a rare but devastating illness with no satisfactory treatments and a typical survival period of only about five years after diagnosis. But precisely because it’s so dire, drug developers have been scrambling in recent years to test the possibilities of new treatments for the neurodegenerative disease, whose formal name is amyotrophic lateral sclerosis.
Now experts in the ALS field are eagerly anticipating clinical trial updates over the next year or so from large companies and small ones, including two in the Bay area: Cytokinetics (NASDAQ: [[ticker:CYTK]]) of South San Francisco and Neuraltus in Palo Alto.
Drug developers see an unmet need among patients with Lou Gehrig’s disease—a commonly used term for ALS that refers to one of its most prominent victims, the legendary New York Yankees batter who died in 1941. Only about 30,000 Americans are living with ALS in a given year, and about 5,600 are diagnosed annually. That limits the market size for any new treatment, but the FDA offers incentives to drugmakers who tackle orphan diseases that affect fewer than 200,000 people in the United States.
Both Cytokinetics and Neuraltus have recently moved forward with plans for a new round of clinical testing on their experimental ALS drugs. Both companies detected encouraging signs of possible benefits of their drugs in earlier trials. But both small companies need to conduct larger trials to see if those benefits can meet the standard of statistical significance. Neither drug is an attempted cure for ALS, whose cause is not fully understood. But the companies hope to delay its debilitating effects—a steady decline in nearly every aspect of normal physical functioning, from speaking and swallowing to walking and breathing.
“It’s the most horrible disease I think I’ve encountered,’’ says industry veteran Robert Blum, the CEO of Cytokinetics. Patients lose the ability to move while their thinking ability is left intact. “They become prisoners in their own bodies.’’
Because the deterioration is rapid enough to be noticeable from one month to the next, researchers can gauge whether some drugs are making a difference by testing them over a relatively short period of time. Short trials cut down the expense of developing a new drug—an important consideration when financing is tight.
In late October, Cytokinetics opened its Phase IIb trial of tirasemtiv, an agent designed to increase the response of skeletal muscles to nerve impulses like those sent by a person’s brain to lift an arm. Trial subjects will receive the drug for three months. Blum says he expects to have data by the end of 2013. “We believe, based on the mechanism of action, that three months is ample to show an effect,’’ Blum says.
At present, the drug used by about half of ALS patients in the United States is Sanofi-Aventis’s riluzole (Rilutek), which was approved by the FDA in 1995. The drug improves survival times by a few months. But new discoveries about genes associated with ALS have stimulated a search for medicines with greater benefits, says Steve Perrin, CEO of the ALS Therapy Development Institute, a non-profit biotechnology research center in Cambridge, MA, that collaborates with drug companies on ALS studies.
“That has enhanced our knowledge of what might be the druggable targets,’’ Perrin says. His institute collaborates with drug companies on ALS studies.
US sales of riluzole have been estimated at $40 to $50 million. But Perrin says the US market could approach $1 billion for a new drug that could substantially delay the loss of muscle function in ALS patients, or improve survival times. Judging from pricing patterns seen in new drugs for multiple sclerosis, Perrin says, an effective ALS drug might command about $50,000 for a year of treatment.
Among the most-watched of the ALS drug development programs, the first peek at data is expected by early 2013 from Weston, MA-based Biogen Idec, which has completed a 900-patient Phase III trial of its drug dexpramipexole. In a Phase II trial, there were signs that the experimental drug could slow the decline of function and extend survival. Dexpramipexole is designed to bolster the efficiency of the energy-manufacturing units called mitochondria in motor neurons. Biogen Idec licensed the compound from Knopp Biosciences of Pittsburgh, PA.
Perrin says the prospects of other ALS contenders such as Cytokinetics won’t be dimmed if