While the search for new treatments and cures is advancing at breakneck speed, ideas about how to help patients pay for them lag far behind. And Republicans who sometimes laud the N.I.H. as the National Institutes of Hope also support dismantling the Affordable Care Act, which could limit access to the new treatments.

“If we are spending billions to incentivize the development of new drugs, I think we also have to ensure that patients can afford those drugs,” said Representative Jan Schakowsky, Democrat of Illinois. “It is almost cruel to find a cure and then have it priced so high that a patient can’t afford it.”

The challenges facing patients and policymakers were illustrated this past week when a Philadelphia company said it would charge $850,000 for a new gene therapy to treat a rare inherited form of blindness. (The company, Spark Therapeutics, said it would pay rebates to certain insurers if the medicine, given in a one-time injection, did not work as promised.)

Members of Congress have friends, relatives and constituents who suffer from cancer, Alzheimer’s and other diseases, but lawmakers may have less interaction with people who are uninsured and unable to afford doctor visits or prescription drugs.

“Sadly,” said R. Alta Charo, a professor of law and bioethics at the University of Wisconsin at Madison, “the cynic in me says it’s because of the prevalence of selfishness. We all want to know there’s something out there that will cure us if we need it, but many of us are quite reluctant to pay for somebody else to get cured when they need it.”

Sherri J. Bale, a geneticist who worked at the N.I.H. for 16 years before founding GeneDx, a genetic testing company in Gaithersburg, Md., said: “Gene therapy has fabulous promise. We will soon be able to treat and even cure people with genetic diseases where we previously had nothing at all to offer them. But where are they supposed to get the money to pay for these treatments — thousands of dollars a month?”

“What good is the research if all you do is treat people in a clinical trial and publish a few papers?” Ms. Bale asked. “I’m afraid that patients will be left in the lurch.”