CARE-PWS Results Announced on LV-101 for Prader-Willi Syndrome


Within the last week, biotechnology company Levo Therapeutics announced results from the Phase 3 CARE-PWS clinical trial. During the trial, researchers examined the efficacy, safety, and tolerability of LV-101 for patients with Prader-Willi syndrome.

Prader-Willi Syndrome

Resulting from gene mutations on chromosome 15, Prader-Willi syndrome is a rare genetic disorder causing a constant and seemingly insatiable hunger. These gene mutations affect the hypothalamus, a part of the brain which plays a role in hormone regulation. Starting around two years old, patients with Prader-Willi syndrome struggle with not feeling full after eating. Additionally, the disorder often causes physical, mental, intellectual, and behavioral difficulties. An estimated 1 in 16,000 people are born with this disorder.

Symptoms vary but may include:

  • “Floppy” muscle tone
  • Low or poor responsiveness
  • Underdeveloped genitalia
  • A narrow forehead, triangular mouth, and almond-shaped eyes
  • Short, slight stature
  • Insomnia and other sleep-related issues
  • Poor sucking reflex
  • Speech and behavioral difficulties
  • Rapid weight gain
  • Constant food craving or eating

Read more on Prader-Willi syndrome here.


Some researchers believe that the constant hunger associated with Prader-Willi syndrome results from an oxytocin deficiency. As a result, Levo Therapeutics designed LV-101 (intranasal carbetocin) as a selective oxytocin-receptor agonist. The National Cancer Institute defines an agonist as:

A drug or substance that binds to a receptor inside a cell or on its surface and causes the same action as the substance that normally binds to the receptor.

LV-101 uses carbetocin, an analog of oxytocin, to treat Prader-Willi syndrome. In layman’s terms, an analog is a drug or therapeutic that is substantially similar to another substance. In this case, carbetocin is substantially similar to oxytocin. Patients receive LV-101 three times a day, preferably before eating a meal. Outside of Prader-Willi syndrome, carbetocin is approved in over 90 countries worldwide to prevent uterine atony, a potentially fatal pregnancy-related complication. As of right now, the FDA granted LV-101 both Orphan Drug and Fast Track designations.

CARE-PWS for Prader-Willi Syndrome

During the CARE-PWS trial, researchers tested the efficacy of LV-101 for 119 pediatric patients with Prader-Willi syndrome. Participants in the trial were between 7 and 18 years old. First, patients received either LV-101 or a placebo for an 8-week period. Researchers studied changes in hunger, anxiety, and compulsive behaviors. Patients who completed the trial were able to continue for up to 56 weeks, during which time all patients received LV-101.

In the first 8-week period, patients received either a placebo, 3.2 mg LV-101, or 9.6 mg LV-101. Ultimately, researchers noted that 3.2 mg was more effective in reducing symptoms than the larger dose. While neither dose impacted obsessive compulsive behaviors, the 3.2 mg dose was more likely to reduce anxiety. Additionally, researchers found that LV-101 was mostly safe and well-tolerated. However, there were some side effects, which included:

  • Headache
  • Nausea and diarrhea
  • Flushed skin
  • Fever
  • Nasal pain or discomfort
  • Upper respiratory infections
  • Nosebleeds
Jessica Lynn

Jessica Lynn

Jessica Lynn has an educational background in writing and marketing. She firmly believes in the power of writing in amplifying voices, and looks forward to doing so for the rare disease community.

Share this post

Share on facebook
Share on google
Share on twitter
Share on linkedin
Share on pinterest
Share on print
Share on email
Close Menu