WASHINGTON — A long-awaited study has found that two of the main medications for treating opioid addiction are similarly effective, a finding likely to intensify the hard-fought competition between drugmakers seeking to dominate the rapidly expanding opioid treatment market.
The study, funded by the federal government, compared Vivitrol, which comes in a monthly shot and blocks the effects of opioids, and Suboxone, which is taken daily in strips that dissolve on the tongue and contains a relatively mild opioid that helps minimize withdrawal symptoms and cravings.
Researchers found that 52 percent of those who started on Vivitrol relapsed during the 24-week study, compared with 56 percent of those who started on Suboxone.
But the study, conducted with 570 adults addicted mostly to heroin, also found a substantial hurdle for Vivitrol. Because the medication can be started only after a person is completely detoxed from opioids — a process that can take over a week — more than a quarter of the study participants assigned to Vivitrol dropped out before being able to take their first dose. Suboxone can be started shortly after withdrawal symptoms begin, and only six percent of those assigned to take that drug dropped out before taking an initial dose.
Drug manufacturers have been competing fiercely to develop and market medications to treat opioid addictions, which have propelled a steep increase in the number of drug deaths in the United States. Last year, 64,000 Americans died from drug overdoses, up 22 percent from the previous year.
There is significant money at stake. Under a law passed by Congress in 2016, the Trump administration is sending $1 billion to states to deal with the epidemic over the next two years, with directions to prioritize so-called medication assisted treatment. Mr. Trump’s opioid commission recently implored Congress to swiftly appropriate more money.
Suboxone, made by Indivior, is the older, cheaper, and much more widely studied and used of the two medications. The manufacturer of Vivitrol, Alkermes, has tried to catch up by marketing its drug as a cleaner alternative, emphasizing that Vivitrol is the only federally approved addiction medication that does not contain an opioid.
Vivitrol is also the most expensive addiction medication, with Medicaid paying about $500 per shot, according to Alkermes, and private insurers paying $1,000. Suboxone tends to cost a third to half as much. Another addiction medication approved by the Food and Drug Administration, methadone, is much cheaper, but people who take it have to go to specially licensed clinics for their daily dose. The study focused on Vivitrol and Suboxone because both can be prescribed by primary care doctors, although a federal waiver is needed to prescribe Suboxone.
Using free samples and millions of dollars in political donations, Alkermes has pushed for the use of Vivitrol in drug courts and jails, where Suboxone is often not allowed. Vivitrol has won fans among many law enforcement officials who see Suboxone as simply replacing one addiction for another. Suboxone is also more likely to be diverted into a black market, though addiction experts say that people who use it are trying to stave off withdrawal, not get high.
But Alkermes’ strategy has drawn attention from lawmakers and law enforcement officials concerned that it is encouraging misconceptions about Suboxone as it tries to promote Vivitrol.
Last month, Senator Kamala Harris of California, a Democrat, announced a Senate committee investigation into the company’s “sales, marketing and educational” tactics, which she said had attempted to artificially boost sales by stigmatizing treatments like Suboxone.
“It is crucial that treatment approaches rest on sound science and the best judgment of medical professionals — not the marketing and lobbying prowess of the pharmaceutical industry,” she wrote in a letter to Alkermes.
Alkermes also recently acknowledged in a filing with the Securities and Exchange Commission that it is cooperating in an investigation by the Justice Department, though it did not say what the focus was.
Suboxone, which has more market share than any other addiction medication, has also come under scrutiny. Its maker has been sued by 43 state attorneys general who say the company schemed to block generic competition by conspiring with another company to create a slightly different delivery system for the drug.
In a recent earnings report, the company said it was discussing a resolution to a federal investigation regarding its marketing and promotion practices.
The new study, published on Tuesday in The Lancet, was only the second to compare the drugs, and the first in the United States. A study conducted in Norway and released last month had similar results, but it was shorter and included fewer patients.
The study’s authors downplayed the drop-off in the patients assigned to Vivitrol, saying that the difficulty detoxing is already well-known. The pressing question, they argued, was whether the two drugs worked equally well.
“The main finding in my view is the relatively equivalent safety and effectiveness of these two medications,” said Dr. John Rotrosen, a psychiatry professor at New York University School of Medicine and the study’s lead investigator.
But in a commentary that the Lancet published along with the study, David Lott, a professor at the University of Illinois College of Medicine, raised concerns about the problem of getting through detox to start Vivitrol, noting that most study participants who failed to detox long enough to start Vivitrol did relapse.
Dr. Rotrosen and Dr. Joshua Lee, a co-author of the study and an associate professor at New York University School of Medicine, have both led or participated in previous studies for which Alkermes provided medication or funding. Two of the other authors also reported receiving research support and in one case, consulting fees from Alkermes. Indivior donated the Suboxone for the study.
Twenty-eight overdoses were reported during the study, which ran from January 2014 through January 2017. Nine occurred in people who never started the medications. Overdose rates among those who took at least one dose did not differ between the two treatment groups, and most occurred well after the last dose of medication.
Dr. Nora Volkow, the director of the National Institute on Drug Abuse, which sponsored the study, said that for those in danger of relapsing before they can fully detoxify, doctors should promptly prescribe Suboxone or another drug containing buprenorphine, its main ingredient.
In a statement, Alkermes said the study was additional evidence to support more widespread use of Vivitrol, and called its drug “an entirely different approach” to medication-assisted treatment.
The company’s chief medical officer, Craig Hopkinson, said the study underscored the importance of detoxification before starting treatment, and noted that the company is working to develop additional drugs that help with detox.
Neither medication is nearly as widely used as it should be, addiction experts say. Although research has found that medication-assisted treatment reduces overdose deaths and relapse, 85 percent of counties have no opioid treatment program that provides it, according to the president’s commission.
Dr. Volkow said she hoped the study would dispel misperceptions that some doctors have about Vivitrol, including that patients don’t tolerate it well and that it doesn’t work as well with cases of severe addiction. Now, she said, researchers should focus on the most effective ways to detox people so they can start Vivitrol and on determining which medication is best for each individual patient.
“It’s extremely important,” she said. “What patient characteristics can lead me as a physician to determine that this particular individual will do better on one of these medications than the other?”
“We have it for every other area of medicine, but not for the treatment of opioid use disorders.”