What Clinical Trials Are Available for Acromegaly? 17 Are Open, and 3 Have US Sites for Patients

In 1783 a young Irishman named Charles Byrne died in London, 7 feet 7 inches tall and terrified of what would happen to his body. He had reportedly arranged to be buried at sea so the anatomists could not have him. It did not work. The surgeon John Hunter is said to have paid Byrne's friends £500 for the corpse, and the skeleton hung in a London museum for more than 2 centuries (Hunterian Museum, 2023).

In 2011, scientists pulled DNA from Byrne's teeth and found the reason he never stopped growing: a mutation in a gene called AIP that drives growth-hormone tumors of the pituitary gland. The same mutation turned up in 4 living families in Northern Ireland, all descended from a common ancestor who lived roughly 57 to 66 generations earlier (Chahal et al., 2011). Byrne had gigantism, the childhood form of the disease. The adult form, when the tumor starts after the bones stop lengthening, is acromegaly, and one of the studies recruiting today is still looking for families like his.

17 Acromegaly Clinical Trials Are Open, and Most of Them Are Not Testing a New Drug

The 17 figure sounds generous until you read the list. Only 4 of the studies test a new medicine, and 1 of those enrolls healthy young men rather than patients. Many of the rest are observational studies, where researchers follow people on their usual treatment or collect data, scattered across Italy, the Netherlands, Germany, the UK, Turkey, China and Taiwan. 2 are about anesthesia: acromegaly enlarges the tongue and airway, which makes putting in a breathing tube during surgery harder, and researchers in Turkey want better ways to predict and manage that. A group at National Taiwan University Hospital is developing a simple system to recognize the disease earlier, which matters for reasons the next section explains.

For a patient in the United States, the list narrows to 3. Counts come from ClinicalTrials.gov as of September 23, 2026, and they change as sites open, so check the near-you page for today's version.

OXTEND-03 Tests Debio 4126, an Octreotide Injection Given Every 3 Months

Octreotide has treated acromegaly since 1988, and the long-acting version most patients use is a monthly injection. Debiopharm's Debio 4126 is a new formulation of the same drug designed to last 12 weeks, which would cut a year of injections from 12 to 4. The Phase 3 OXTEND-03 trial (NCT06930625) randomized its first patient in late 2025 and plans to enroll about 120 adults across roughly 75 sites in 21 countries (Debiopharm, 2025).

It is built for people whose acromegaly is already controlled on octreotide or lanreotide injections, with normal IGF-1 levels (the blood marker doctors use to track growth hormone). Some participants will get placebo during the blinded phase, and the main question is whether IGF-1 stays in the normal range at week 36. The 10 US sites are Cedars-Sinai in Los Angeles, Northwestern in Chicago, Harvard in Boston, Washington University in St. Louis, Palm Research Center in Las Vegas, NYU in New York, Cleveland Clinic, Ohio State in Columbus, Oregon Health & Science University in Portland and Thomas Jefferson in Philadelphia (ClinicalTrials.gov, 2026).

MAR002 Tests a Growth Hormone Receptor Antibody in Phoenix, Columbus and San Antonio

Marea Therapeutics is taking the other route. Instead of lowering growth hormone, MAR002 is an antibody that blocks the growth hormone receptor, the same target as the daily injection pegvisomant (Somavert), but engineered to last much longer. In its first results in healthy volunteers, a single dose cut IGF-1 by up to 52% at its peak and held it more than 45% lower out to day 43. Data presented in June showed suppression of up to 64%, and Marea says the drug levels could support dosing every 2 weeks to monthly (Marea Therapeutics, 2026). Its patient study, listed on ClinicalTrials.gov as Phase 2 (NCT07641179) and described by the company as the start of a Phase 2/3 program, is recruiting adults 18 to 75 at St. Joseph's Hospital in Phoenix, Endocrinology Associates in Columbus and Consano Clinical Research in San Antonio.

A separate MAR002 study in Tempe, Arizona shows up in acromegaly searches too. It enrolls healthy men aged 18 to 40 and is not open to patients.

The NIH Pituitary Tumor Study in Bethesda

The oldest study on the list, NCT00001595, is run by the National Institute of Child Health and Human Development at the NIH Clinical Center in Bethesda, Maryland. Titled "An Investigation of Pituitary Tumors and Related Hypothalamic Disorders," it enrolls people from age 2 to 70 with pituitary tumors, a group that includes growth-hormone tumors, so it is open to children as well as adults. It does not test a specific new drug. The study contact listed on ClinicalTrials.gov can say whether a particular case fits.

Acromegaly Studies Opening Soon or Only Abroad

China: CSPC long-acting octreotide (NCT07623824)

A Phase 3 trial of a new octreotide formulation, not yet recruiting.

UK: PRESTO proton beam trial (NCT07813351)

A Phase 3 comparison of dose-escalated proton beam radiotherapy against standard radiotherapy for hormone-secreting pituitary tumors, not yet recruiting.

UK: FIPA genetics study (NCT00461188)

Barts and The London's study of families with inherited pituitary tumors, the research line that found Byrne's mutation. Recruiting at 3 UK sites.

Germany and UK: Oclaiz observational study (NCT07583563)

Camurus follows patients using its monthly self-injected octreotide, already approved in Europe. Recruiting at 6 sites.

Netherlands: ketogenic diet (NCT06949891)

Erasmus Medical Center in Rotterdam tests whether a ketogenic diet changes acromegaly control.

Italy: 4 studies

Switching from first-generation somatostatin drugs to pasireotide, pasireotide and bone health, hand and foot changes under treatment, and a study of hormones and body fat that has not opened yet.

Acromegaly changes a face so slowly that the people who see it every day never notice. Rings stop fitting. Shoes go up a size. A jaw moves forward, teeth drift apart, and the explanation offered at each appointment is age, weight or arthritis. The largest registry of patients at diagnosis, 3,173 people from 10 countries in the Liège Acromegaly Survey, put the median delay from first symptoms to diagnosis at 10 years for women and 8 years for men (Petrossians et al., 2017).

By the time the diagnosis comes, the disease has usually been at work for years. In the same registry 71.8% of tumors were already macroadenomas, larger than 1 centimeter, 27.5% of patients had diabetes, 28.8% had high blood pressure and 25.5% had sleep apnea, a figure that rose to 69% at centers that tested everyone with an overnight sleep study. The survey did find delays shrinking over the decades, but patients were also older when they finally got a name for it, with a median age of 45 at diagnosis.

“Scientists estimate that about 3 to 14 of every 100,000 people have been diagnosed as having acromegaly.”

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

The pandemic added a strange twist. In August 2026 doctors at the University of Osaka described a 74-year-old woman referred for diabetes that would not come under control, with an insulin resistance that did not match her weight. A physical exam finally caught changes in the lower half of her face that mask-wearing had concealed, and testing confirmed acromegaly (Sakaue et al., JCEM Case Reports, 2026). The recognition study recruiting in Taiwan is part of the same push to catch the disease before a decade goes by.

Charles Byrne's AIP Gene and Who Should Be Tested for It Today

Harvey Cushing, the pioneering neurosurgeon, examined Byrne's skeleton in 1909 and noted the enlarged bony pocket at the base of the skull where the pituitary gland sits (Chahal et al., 2011). A century later the NEJM team connected that tumor to living people. In January 2023 the museum's trustees announced that Byrne's skeleton would not go back on display when the Hunterian reopened, though the museum kept it for research into acromegaly and gigantism rather than burying it (Hunterian Museum, 2023).

Most acromegaly is not inherited. More than 9 in 10 cases come from a tumor that arises on its own. The genetic cases matter because they strike young and run in families. According to GeneReviews, AIP variants are found in about 10% to 15% of families with inherited pituitary tumors and about 40% of families where every tumor makes growth hormone, and the median age at diagnosis in AIP carriers is 23 (GeneReviews, 2025). The same review recommends suspecting an inherited cause when someone has a pituitary tumor diagnosed before age 18, a growth-hormone macroadenoma before age 30, or more than 1 relative with a pituitary tumor. In those families, relatives can be tested for the specific variant already found.

Acromegaly Treatments in 2026, and How Well Each One Worked in Its Own Trials

Surgery through the nose, called transsphenoidal surgery, comes first for most patients. In experienced hands it puts more than 85% of microadenomas into remission, but only 40% to 50% of macroadenomas (Katznelson et al., Endocrine Society guideline, 2014). With nearly 3 in 4 tumors already large at diagnosis, many patients end up on medication afterward, and the options have multiplied.

The Signifor number looks low for a reason. PAOLA enrolled only people whose disease stayed uncontrolled on the standard drugs, the group whose acromegaly is hardest to control, and 20% on the 60 mg dose reached both targets against none of those kept on their previous drug (FDA prescribing information). Pegvisomant (Somavert) is missing from the chart because its label reports average IGF-1 drops, 27% to 63% depending on the daily dose against 4% on placebo, instead of the share of patients reaching normal. It works on the receptor rather than the tumor, which makes it the usual next step when somatostatin drugs fall short.

Oclaiz Faces an FDA Decision on December 18th After 2 Complete Response Letters

Camurus's Oclaiz (CAM2029) is octreotide in a monthly depot that patients inject under the skin themselves, closer to an insulin pen than a trip to the clinic. Europe approved it as Oczyesa on June 30, 2025. The FDA has turned it down twice, most recently on June 10, 2026. That letter cited findings from an inspection at a third-party manufacturing site and raised no concerns about efficacy or safety (Camurus, 2026). The FDA accepted the resubmission on July 17 and set a new action date of December 18, 2026. The decision page will carry the outcome.

What Acromegaly Patients Say Treatment Still Misses

In January 2021 the patient group Acromegaly Community hosted a patient-focused drug development meeting, a format built to let the FDA hear directly from people living with a disease. 304 people attended, 128 of them patients, and a team of endocrinologists later published the results, with Acromegaly Community's Jill Sisco among the authors (Shah et al., Frontiers in Endocrinology, 2025).

Anxiety or depression affected 75% of patients who answered. About half said the disease had cut into their social life, and more than a third said it had affected school or work. One patient's comment, recorded in the paper, is the kind that does not show up in an IGF-1 report.

“I ended up losing my job that I adored.”

Patient comment, Acromegaly Community meeting, published in Frontiers in Endocrinology (Shah et al., 2025)

That gap is worth raising at every visit. A clinical trial is one way to get closer monitoring and a newer drug; the patient group, Acromegaly Community, is another way to find people who have lived through the same slow years. For the practical side of moving from monthly shots to a pill, the Palsonify one-year post covers the switch in detail.