The Leclaire brothers of Pembroke, Mass., were born with Duchenne muscular dystrophy, a rare but deadly neurodegenerative disease. For the past three years, Max, 12, has taken eteplirsen, an experimental drug obtained through a clinical trial. Eteplirsen has given Max the ability to run again. His brother Austin, three years older, didn’t qualify for the same trial. The boys’ mother, Jenn McNary, has been stymied in her attempts to get eteplirsen for her older son by U.S. Food and Drug Administration protocols that restrict access to drugs in clinical trials. “Anyone who is terminally ill ought to be able to try anything that might save his life without interference from the FDA,” McNary says.

Many agree, and advocates for more liberal access to experimental drugs pressured legislatures in Arizona, Colorado, Missouri, Louisiana and Michigan to pass “right to try” laws in 2014. Those statutes allow dying patients who have exhausted all other treatment options to bypass the FDA and gain access to non-approved drugs, as long as they have the consent of their physicians and the drugs’ manufacturers. Similar bills are expected to be introduced in a dozen additional states during the next year, according to Victor Riches, vice president of external affairs at the Goldwater Institute, an advocacy group in Phoenix that drafted model right-to-try legislation.

Not everyone is enthusiastic about this trend. One concern about wider access to unapproved drugs is that they may do more harm than good. Fewer than one in 10 drugs in the first stage of clinical trials ever wins FDA approval. “These laws rest on the faulty assumption that there are all sorts of miracle drugs out there that can save the lives of terminally ill patients if only the FDA would get out of the way,” says David Gorski, a professor and surgical oncologist at the Wayne State University School of Medicine in Detroit, and a managing editor of the blog Science-Based Medicine.

Pharmaceutical companies will have a choice whether or not to provide their drugs, and several factors weigh against their participating. The laws could weaken the current trials development process because patients might opt to bypass the official trial’s inherent risk of receiving a placebo in favor of a more certain right to try. Also, those who receive the experimental drugs outside the trials could experience adverse effects, potentially setting back the approval process. There’s also uncertainty about the manufacturer’s liability under the new laws, though some counter that the drugs have been in at least a phase 1 clinical trial, making them subject to FDA oversight measures.

The FDA also has a program already in place to expand access to experimental drugs. Advocates for the new laws, however, counter that it can take five to six months to process requests from patients and their physicians, a gauntlet that restricts access to fewer than 1,000 patients a year, according to the Goldwater Institute.

Arthur Caplan, director of medical ethics at New York University Langone Medical Center, points to a final drawback of right-to-try legislation. “The laws do nothing about the real problem, which is money,” Caplan says. Experimental drugs are often not covered by insurance.

Indeed, even if Massachusetts had a right-to-try law, eteplirsen’s $200,000 annual cost would be prohibitive for the McNary family. “If there’s no way to pay for a new drug, then the laws don’t matter,” says McNary.