PTH-independent Effects of Encaleret
brief summary
Background: Parathyroid glands in the neck make a hormone that keeps blood calcium levels stable. Sometimes these glands are damaged or removed during neck surgery. This can lead to a condition called postsurgical hypoparathyroidism (PSH). People with PSH have low levels of calcium in their blood. Calcium and vitamin D pills can help them keep their blood calcium levels steady. But this can increase calcium in the urine and result in kidney problems. New treatments for PSH are needed. Objective: To test a drug (encaleret) in people with PSH. Eligibility: People aged 18 or older who have PSH. Design: Participants will be in the study for 6 months. They will have a screening visit and a treatment visit. Screening will take up to 2 days. Participants will have a physical exam. They will have blood and urine tests and tests of their heart function. They will have an ultrasound of their kidneys; they will lie on a table for 15 to 30 minutes while a wand is moved over their back. Treatment will require participants to stay in the clinic for 7 days and 6 nights. They will take the study drug (encaleret) by mouth twice a day for 5 days. They will have a small, flexible tube inserted into a vein; this will remain in place during the visit. Blood samples will be taken through the tube 4 to 9 times each day. Participants urine will be collected. Participants will have follow-up blood tests one (1) week after leaving the clinic. They will have three (3) follow-up phone calls.
detailed description
Study Description:
This will be a single-site, proof-of-principle, open-label study to explore the PTH-independent effects of encaleret on calcium homeostasis in participants with low or undetectable PTH levels as a result of neck surgery (PSH).
Objectives:
Primary Objective:
-Evaluate the PTH-independent effects of encaleret on renal calcium handling in participants with PSH.
Secondary Objectives:
-Evaluate the ability of encaleret to normalize blood calcium while maintaining a normal urinary calcium in participants with PSH.
Primary Endpoint:
\-- Percent change in Fractional Excretion of Calcium (FECa) from baseline (Day -1) to the final day of treatment (Day 6 or the last measurement while on encaleret). FECa calculated using fasting blood levels and spot urine collection.
Secondary Endpoints:
\-- Proportion of participants who achieve a concomitant normal or elevated fasting blood calcium (albumin-corrected calcium\>8.5 mg/dL) and a normal 24-hour urinary calcium level (\<250 mg/24 hours for women, \<300 mg/24 hours for men) on encaleret at any point between day 1 and day 5.
official title
Phase 2 Study of the PTH-Independent Effects of Encaleret on Mineral Homeostasis in Subjects With Post-Surgical Hypoparathyroidism (PSH)