The Republican health care bill that’s already encounteringstiff opposition from hospitals, doctors, and patients now hasanother group worried: rare-disease drugmakers and the patients whoneed those high-priced treatments.

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The proposal, which the Senate could vote on as soon as nextweek, would give states leeway to allow the return of healthcoverage caps -- called lifetime limits -- that were banned underObamacare.

That could allow insurers, including those that offer plansthrough employers, to cut off reimbursements once an insured personspends $1 million to $2 million on prescription drugs. Withexpensive rare-disease drugs, that can happen quickly.

Treatments for rare diseases brought in $114 billion inworldwide sales last year, according to Evaluate Ltd., a lifesciences data company, and drugmakers big and small areincreasingly banking on them to boost revenue.

If insurers are permitted to stop paying for them at a certainpoint, the burden may fall to patients, and ultimately drugcompanies will pick up the tab for those who can’t afford the cost,said Steve Holtzman, chief executive officer of closely-heldDecibel Therapeutics Inc.

“Where a patient exhausts the limit and can’t pay, you’re usingthe patient assistance programs and providing the drug for free,”said Holtzman, whose company is developing treatments for hearingloss.

Last year, there were 16 drugs that cost more than $200,000 ayear per U.S. patient, including blockbusters like Shire Plc’shemophilia therapy Advate and Jazz Pharmaceuticals Plc’s narcolepsydrug Xyrem, according to Evaluate.

Sanofi, Roche Holding AG, and Vertex Pharmaceuticals Inc.also have pricey drugs in that range. Biogen Inc.’s new drug for adeadly muscle disease costs $750,000 for the first year of therapy,and $375,000 a year thereafter.

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A patient using Alexion Pharmaceuticals Inc.’s Soliris treatmentfor rare blood disorders, which costs around $500,000 to $700,000 ayear, could take less than three years to blow through a $2 millionlifetime cap. Before Obamacare, about 16 percent of Americansworkers had lifetime limits at or below that level.

Alexion is working to ensure that any Obamacare replacement willcontinue to ban insurance limits, according to company spokeswomanKim Diamond.

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The threat of coverage caps is another challenge for the GOPbill, which the nonpartisan Congressional Budget Office estimatedwould increase the number of people without insurance by 22million. The bill has encountered resistance within the Republicanparty and a Quinnipiac University poll last week indicated thatjust 16 percent of Americans support it.

Path offered

The Senate bill doesn’t explicitly remove the ban on lifetimelimits, yet it offers a path to restore them. It allows states tocut certain categories from a list of required coverage areas,called essential health benefits, and removing drug coverage fromthat list would allow insurers to cap their medicationbenefits.

Even if states were to take those steps, the Department ofHealth and Human Services would likely head them off throughregulations, according to Thomas Miller, a fellow at theconservative American Enterprise Institute.

Politically, bringing back lifetime limits is “a suicidemission,” Miller said in a telephone interview. “It’s aprojection of what could happen, but it’s not a projection ofwhat’s going to happen.”

Costs of care

Still, patients and their families are concerned thatlifetime limits would restrict access to expensive drugs as well asother treatments. Costs for Duchenne muscular dystrophy couldquickly push patients over their caps and out of coverage, CarrieMiceli, whose son has the deadly muscle condition, said in aninterview.

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“Lifetime caps would really, truly be horrible for ourcommunity. We wouldn’t have access to the basic care we have now,”said Miceli, who’s also co-director of the Center for DuchenneMuscular Dystrophy at the University of California, LosAngeles.

“It’s a disease where you should be consulting and using a teamof seven to eight clinical experts a year -- testing and follow-upand equipment.”

The limits could also discourage research on approaches likegene and cell therapies for rare-disease sufferers -- treatmentsthat some analysts have said could cost $1 million or more forpotential cures.

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“It’s definitely going to start becoming a factor in thinkingabout how you choose programs to develop,” said Bassil Dahiyat, CEOof rare-disease drugmaker Xencor Inc.

“It will certainly be a dampener, especially on the newtechnology approaches like gene therapy, the cell therapies thatare not quite ready for prime time.

Trump factor

Some Republican governors have asked Congress for the power tochange their states’ coverage requirements, and the nonpartisanCongressional Budget Office estimates that under the GOP bill, halfof U.S. residents would live in states with diminished essentialhealth benefits.

“Right away there will be several that will do it,” saidSabrina Corlette, a professor at Georgetown University’s Center onHealth Insurance Reforms. “And then more could come underpressure.”

President Donald Trump, who called an earlier version of thehealth overhaul “mean,” would likely oppose reviving the caps,according to John Maraganore, CEO of Alnylam PharmaceuticalsInc.

“Those are provisions that are in the ‘mean’ category, and thegoal of the president is to try not to be ‘mean,’” said Maraganore,who’s also chair of the Biotechnology Innovation Organizationindustry group, in an interview. Trump has supported the currentSenate legislation, and last month suggested that Congressrepeal all of Obamacare before setting up a replacement.

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BIO says it has no formal position on the Senate bill, andPharmaceutical Research and Manufacturers of America,the biggest drug industry trade group, said it supportsretaining patients’ access to medication.

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