A Phase 3 interventional study of eneboparatide and Placebo in Chronic Hypoparathyroidism, Endocrine System Diseases and Parathyroid Diseases, sponsored by Alexion Pharmaceuticals, Inc.. Active, not recruiting at 54 sites in 13 countries. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2025-09-29.
Sponsored by Alexion Pharmaceuticals, Inc. (part of AstraZeneca) · Phase 3, Interventional, and Treatment
Among 43 studies in Hypoparathyroidism with a site in United States — 8 open to participants now, 12 under way, 5 of them phase 3. Hypoparathyroidism · United States.
Among the 43 studies in Hypoparathyroidism with a site in United States, this one has the largest planned enrollment of the 34 interventional ones, is one of 3 that started in 2023, is one of 13 in phase 3, reaches primary completion later than 0 of the 11 other live ones, and was the 34th registered.
128 studies on the registry are indexed under Hypoparathyroidism; 30 are open to participants now.
This study's planned enrollment of 165 is above the median of 50 across 77 interventional studies indexed under Hypoparathyroidism.
Browse Hypoparathyroidism studies →8 of the 43 studies in Hypoparathyroidism with a site in United States are open now, in 2 countries. Each count lists the studies.
Of the 26 Hypoparathyroidism studies recruiting now, 19 (73%) set no upper age limit and 5 (19%) stop at 75 or younger; 5 take children under 18; 3 take healthy volunteers.
This study: 18 Years to 80 Years · all sexes · no healthy volunteers.
The full table on the hub →43 studies; the count open now beside each. This study's row is marked.
First in 1991; this study’s year is marked. 3 started in 2023.
Median enrollment 41 across the 34 interventional studies, 95 across the 9 observational. Of the 29 that completed or were terminated, 22 (76%) have results posted.
27 of 43 have an industry lead sponsor. The 10 most frequent:
Alexion Pharmaceuticals, Inc. is the lead sponsor of 255 studies on the registry; 23 are open to participants now.
Of its 101 completed or terminated interventional studies of FDA-regulated products, 75 (74%) have results posted.
Alexion Pharmaceuticals, Inc. has 2 studies filed under Hypoparathyroidism — fewer than ten, so there is no comparison to draw.
3 of the studies in Hypoparathyroidism with a site in United States that are under way reach primary completion within a year, 1 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT07081997Phase 3Ascendis Pharma Bone Diseases A/SA Phase 3 Randomized Clinical Trial to Investigate the Safety and Efficacy of Palopegteriparatide at Doses Greater Than 30 μg/Day in Adult Participants With Hypoparathyroidism | 2027-06 |
| NCT05793853Columbia UniversityHypoparathyroidism Natural History Study | 2026-12 |
| NCT07264634Ascendis Pharma A/SA Study to Assess the Amount of Palopegteriparatide in Breast Milk of Lactating Females Requiring YORVIPATH® (Palopegteriparatide) | 2027-08 |
Among the 43 studies in Hypoparathyroidism with a site in United States, from their registry updates:
This study is investigating the safety and efficacy of eneboparatide (AZP-3601) in patients with chronic hypoparathyroidism (cHP).
During the first 24 weeks of the trial, participants will be randomized to receive eneboparatide or placebo. Study treatment is blinded: patients and doctors will not know which group each patient has been randomized to. All patients will start with a fixed dose of study treatment (eneboparatide or placebo), administered subcutaneously with a pre-filled pen. Study treatment will be individually titrated.
After completion of the first 24 weeks, patients will be treated in the open label extension part of the study for 132 weeks. During this phase, all patients (including patients that were in the placebo group) will receive eneboparatide.
128 studies on the registry are indexed under Hypoparathyroidism; 30 are open to participants now.
This study's planned enrollment of 165 is above the median of 50 across 77 interventional studies indexed under Hypoparathyroidism.
Browse Hypoparathyroidism studies →Alexion Pharmaceuticals, Inc. is the lead sponsor of 255 studies on the registry; 23 are open to participants now.
Of its 101 completed or terminated interventional studies of FDA-regulated products, 75 (74%) have results posted.
First submitted after Alexion Pharmaceuticals, Inc. became part of AstraZeneca.
Compared within Hypoparathyroidism, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Endocrine System Diseases. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Prior to start of treatment:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Starting dose of 20 mcg; Administered once daily by subcutaneous injection
Combination Product: eneboparatide
Administered once daily by subcutaneous injection
Combination Product: Placebo
Supplied as a solution (concentration of 250 mcg/mL or 500 mcg/mL) in single-patient-use prefilled pens
Also known as: AZP-3601
Placebo is supplied as a solution (containing the excipient solution for eneboparatide) in single-patient-use prefilled pens
Efficacy - Primary Endpoint
After 24 weeks of treatment, the proportion of patients in the eneboparatide treatment group vs. placebo: * Achieving complete independence from active vitamin D; * Achieving independence from therapeutic doses of oral calcium (i.e. taking oral elemental calcium supplements ≤600 mg/day); and * With albumin-adjusted serum calcium within the normal range (8.3 to 10.6 mg/dL).
Time frame: 24 weeks
Hypercalciuria
Proportion of patients who had hypercalciuria at baseline and normalize 24-hour urinary calcium excretion level (i.e., achieve \<250 mg/24 hours for females or \<300 mg/24 hours for males)
Time frame: 24 weeks
Change from baseline in the HPT-DD-SE - Physical Domain score
Change from baseline in patient's symptoms, as assessed by the average weekly HPT-DD-SE physical domain score in the eneboparatide treatment group vs. placebo
Time frame: 24 weeks
Change from baseline in the HPT-DD-SE - Cognitive Domain score
Change from baseline in patient's symptoms, as assessed by the average weekly HPT-DD-SE cognitive domain score in the eneboparatide treatment group vs. placebo
Time frame: 24 weeks
Change from baseline in the HPT-LIQ - Physical Functioning Domain score
Change from baseline in the HPT-LIQ Physical Functioning domain score, in the eneboparatide treatment group vs. placebo
Time frame: 24 weeks
Change from baseline in the SF-36 Physical Functioning subscore
Change from baseline in the SF-36 Physical Functioning subscore in the eneboparatide treatment group vs. placebo
Time frame: 24 weeks
Ran from Jun 2023 to primary completion in Nov 2024, 17 months.
Of 15 phase 3 interventional studies under Hypoparathyroidism, half reached primary completion within 17 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 86. This study's 17 months is close to that.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.
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Alexion Pharmaceuticals, Inc. →