Federal regulators this week approved a new schizophrenia drug from Alkermes PLC, an Irish biotech company with executives based at its Waltham campus.
The drug, Aristada, is a long-acting version of Abilify, a best-selling antipsychotic that earned more than $9 billion worldwide last year, according to IMS Health, before losing patent protection in April.
Administered by injection, Aristada dissolves slowly over four to six weeks, negating the need for daily pill-taking. As many as half of schizophrenia patients on oral antipsychotics don’t end up taking their medications as prescribed.
Aristada “may be a good option for people who have difficulty taking medication regularly,” said Dr. Joseph Stoklosa, medical director of the schizophrenia and bipolar disorders unit at McLean Hospital.
Alkermes, which specializes in making extended-release versions of many generically available drugs, is not the only company with a long-acting antipsychotic on the market.
Since 2013, Otsuka Pharmaceutical Co., the Japanese company behind Abilify, has sold a once-monthly form of its blockbuster antipsychotic, known generically as aripiprazole. Long-acting versions of Zyprexa, Risperdal, and other commonly prescribed schizophrenia drugs are available, too.
Aristada will cost about $1,500 a month, comparable to other long-acting antipsychotics.
The new drug’s competitive advantage could come from its dosing and length of action: Doctors can choose one of three possible drug concentrations, and the highest dose can last as long as six weeks.
“Patients don’t always come back right at one month,” said Dr. Elliott Ehrich, executive vice president of research and development and chief medical officer at Alkermes.
To make the drug last longer, Alkermes scientists added a little fatty tail to each aripiprazole molecule. Because fat and water don’t mix well — as any maker of salad dressing knows — the addition of fat means that the drug dissolves more slowly. And as each molecule dissolves, an enzyme in the body clips off the fatty tail, allowing the drug to do its job.
The formulation also means that Aristada can be sold as a liquid in prefilled syringes, unlike Otsuka’s Abilify Maintena, which comes as a powder that must be reconstituted before administration.
“You basically put on the needle, shake it quickly, and then inject,” said Alkermes’ chief financial officer, Jim Frates. “Bringing a new, easy-to-use, flexible dosage form of aripiprazole is something physicians and patients are going to benefit from.”
The FDA based its approval in part on an international trial of 622 people with schizophrenia who received either once-monthly injections of Aristada or a placebo. At the end of the 12-week trial, participants given Aristada experienced significantly fewer delusions, hallucinations, and other disease symptoms compared to those who received dummy shots. The most common side effects included insomnia, headaches, and anxiety.
Biren Amin, an analyst at Jefferies, forecasts sales of Aristada will reach $286 million by 2018.