Who Runs Your Rare Disease's Clinical Trials, and Why It Changes What You'll Be Offered

Two diseases inflame the same large arteries. Giant cell arteritis mostly strikes people over 50, and since 2017 it has had an FDA-approved drug, then a second one in April 2025, both proven in trials that drug companies paid for. Takayasu arteritis, the form that mostly strikes women between about 15 and 40, has never had a drug approved for it in the United States. On October 15, 2026, Trial Friend counted every trial open to new patients in each disease and who runs it. Giant cell arteritis had 45, Takayasu 26, and in neither disease was a single one led by a drug company.

That pattern repeats across the 229 rare conditions Trial Friend tracks. Drug companies are the lead sponsor of 1,866 of the 7,541 trials open to new patients, which is 1 in 4. In 51 conditions they run none at all. For a family searching for a trial, the sponsor decides more than the name at the top of the listing. It shapes whether the study tests a treatment or only collects data, whether the drug is new or borrowed from another disease, how many sites are in the United States, and how likely an approval is at the end.

Why Giant Cell Arteritis Got 2 Approved Drugs and Takayasu Arteritis Got None

Giant cell arteritis got its drugs because 2 companies ran the trials. Genentech's GiACTA study of 251 patients showed that Actemra (tocilizumab) with a 6-month steroid taper kept 56% of patients in sustained remission at 1 year against 14% on placebo, and the FDA approved it for the disease on May 22, 2017, according to Genentech's announcement. AbbVie's SELECT-GCA trial then showed 46% sustained remission on Rinvoq (upadacitinib) against 29% on placebo, and the FDA added giant cell arteritis to Rinvoq's label on April 29, 2025, according to AbbVie. Both companies already sold the drug for rheumatoid arthritis and had a large adult population to enroll, which is the kind of situation that gets a company trial funded.

Takayasu arteritis is the same kind of inflammation in a smaller, younger group of patients, and no company has run a trial of a new drug there to completion. In Trial Friend's count, 15 of its 26 open studies are observational, meaning they follow patients and collect blood, scans and records without testing a treatment. The 11 treatment trials test prednisone, methotrexate, tofacitinib, adalimumab and tocilizumab, drugs that already exist for other diseases, most of them run by hospitals in Shanghai, Paris and Philadelphia. Only 4 of the 26 have a site in the United States. AbbVie does have a Takayasu trial of upadacitinib, SELECT-TAK, but it is closed to new patients and its ClinicalTrials.gov record, updated February 2026, estimates completion in August 2028.

The giant cell arteritis side shows the second half of the story. Once Actemra and Rinvoq were approved, the company trials ended, and the 45 studies still open are run by hospitals and universities, 32 of them observational. One reading of that pattern is that a company runs the trial it needs for an approval and the company-run research ends there, while the longer work of learning how to use the drug well, in which patients and for how long, falls to academic researchers with grants.

Trial Friend's count comes from ClinicalTrials.gov, which asks every registered study to name a lead sponsor and class it as industry, NIH, another government agency, a network, or other, which covers hospitals, universities and foundations. The chart takes the trials open to new patients in 16 of the 229 conditions Trial Friend tracks, checked October 15, 2026, and shows the drug-company share of each. The 2 numbers beside each strip say how many of those trials only collect data and how many have at least 1 US site.

The top of the chart is where the 2026 approvals came from. Trutakna and the full approval of Fabhalta for IgA nephropathy, Mimrylo for polycythemia vera and the newest myasthenia gravis drugs all came out of company-run trials in diseases where companies run a third to four-fifths of the research. The bottom of the chart is a different world, and a family there needs to read trial listings differently.

What a Rare Disease Trial Looks Like When No Drug Company Is Paying

When a drug company is not paying, most of a disease's open trials collect data rather than test a treatment. In the 7 conditions in the chart with no company sponsor, 82 of 131 open studies are observational. Those studies matter, because a natural history study is often what makes a later drug trial possible, and joining one keeps a patient on a research center's radar. It will not treat anyone, though, and a listing that says "recruiting" can raise hopes it was never designed to meet.

The treatment trials that do exist usually test an old drug for a new job. Takayasu's are methotrexate, prednisone and arthritis biologics. Moyamoya's test aspirin. Williams syndrome's test methylphenidate, fluoxetine and risperidone, medicines that have been on the market for decades. Investigator-initiated trials like these can be run on a hospital's budget because the drug already exists, and that has a practical upside for a family. The drug being tested can often be prescribed today, off-label, without waiting for the trial to finish, which is a question worth asking a specialist directly.

Sites are the third difference. Company trials recruit at dozens of centers because enrollment speed is the whole budget. Academic trials recruit where the investigator works. Marfan syndrome's 11 open studies include 2 with a US site; its biggest sponsors are a hospital in Toulouse and a research institute in Milan. Moyamoya's 20 include 2 in the United States, with 7 run by Beijing Tiantan Hospital. Fanconi anemia is the exception that shows it is a choice rather than a rule: 12 of its 14 open studies have a US site, because American transplant centers have led that disease for 30 years.

Marfan Syndrome and Losartan, a Treatment Answer No Drug Company Paid For

Marfan syndrome weakens the aorta, the large blood vessel that carries blood out of the heart. Over the years the aorta can stretch and tear, and that is what most often kills people with the disease. For decades, doctors protected the aorta with a beta-blocker, a cheap blood pressure pill that slows the heart so each beat puts less strain on the vessel. Then in 2006, researchers at Johns Hopkins found that a different blood pressure pill, losartan, stopped the aorta from stretching in mice with Marfan syndrome (Habashi et al., 2006). It looked like a drug that might work on the disease itself, not only take pressure off the heart.

No drug company tested it, because losartan was already a generic and a trial in Marfan syndrome could never earn back its cost. The NIH ran the trial instead, through its Pediatric Heart Network, with help from the FDA's rare disease office and the National Marfan Foundation. From 2007 to 2011, 21 hospitals enrolled 608 children and young adults. Half took losartan and half took the beta-blocker atenolol for 3 years. The result came out in 2014: losartan was not better. Both pills slowed the stretching of the aorta about the same, and the 2 groups had the same rates of surgery, tearing and death (Lacro et al., 2014).

That is the best a trial with no company behind it can do. It did not produce a new drug, nobody asked the FDA to approve anything, and no drug label names Marfan syndrome today, which is why the treatment and trial gap dataset lists the disease with 0 approved medicines. What families got was an answer their cardiologist could use right away: 2 cheap generic pills, either one a reasonable choice, prescribed off-label because a 608-patient trial showed they work. The 11 Marfan studies open today work the same way. Hospitals in Toulouse, Milan and Boston run them, 7 only collect data, and 2 have a site in the United States.

Do Academic Rare Disease Trials Finish and Lead to Approvals?

They finish less often. A 2019 study in PLOS Medicine by Carolyn Rees and colleagues at Boston Children's Hospital followed 659 randomized rare disease trials registered from 2010 to 2012. Industry was the primary funder of 50% of them, academic institutions 28%, and 30% of all the trials were stopped before completion, most often because too few patients enrolled. After adjusting for trial design, trials paid for by hospitals and medical centers had about 2.4 times the odds of being stopped compared with industry-funded trials (Rees et al., 2019). That study counted randomized trials by who paid, while Trial Friend counts open trials of every kind by who leads them, so the 2 figures describe different things and neither is a trend line from the other.

The approvals follow the money too. Every one of the 19 rare disease approvals on Trial Friend's FDA calendar since July 2026 rested on a company-run pivotal trial, because an approval needs a sponsor to run that trial and file the application, and in rare disease that sponsor is almost always a company. A hospital can prove that an old drug helps, and doctors can prescribe it on that evidence, but it rarely leads to a label. For a family, the honest reading of a disease with no company trial is that an approval is not close, while useful treatment may already be in a doctor's reach.

Public money fills some of the gap. The NIH's Rare Diseases Clinical Research Network began its fifth 5-year funding cycle in 2025 with $31.6 million for the fiscal year, covering 23 consortia and a data center, and since 2003 the network's consortia have studied more than 280 rare diseases, according to the network. Those consortia run many of the natural history studies in the chart. Takayasu arteritis was studied for 15 years by the network's Vasculitis Clinical Research Consortium, based at the University of Pennsylvania, which has since graduated from NIH network funding and continues as an independent group.

What to Do If Your Rare Disease Has No Drug Company Trial

Start by reading the sponsor line on each trial listing on your disease's Trial Friend page, then sort the open studies into 2 groups: those that test a treatment and those that collect data. Take the treatment trials to your specialist with a direct question, which is whether the drug being tested can be prescribed for you now, outside the trial, and what the evidence for it looks like. Join a natural history study if one is open, because the registries and biobanks those studies build are what a company looks at before it decides a disease is worth a trial, and that choice gets made on the strength of the data patients have already given.

Watch the 51-condition list, too. It changes. Ataxia-telangiectasia was on it until IntraBio's trial produced Aqneursa's approval on September 18, 2026, and Alexander disease left it when Ionis won approval for Zanvastro on September 3. The treatment and trial gap dataset is rebuilt with each trial census, with every past edition kept, so a family can see whether a company has arrived in their disease since the last check. Signing up for trial alerts on a disease page does the watching for you.

Questions Families Ask About Who Runs Rare Disease Trials