CJC-1295 vs Somapacitan
It is sold as an injection to build muscle, burn fat and slow ageing. Small trials show it raises growth hormone for days, but none show it changes muscle or fat. A once-a-week growth hormone shot that replaces daily shots. Controlled trials show it works as well as daily doses.
Somapacitan has the stronger evidence, grade A (strong human evidence) against grade B for CJC-1295. CJC-1295: Not approved. Somapacitan: FDA approved.
Evidence
BSome human evidence
AStrong human evidence
Human studies cited
Animal or cell studies cited
Why the grade
Two randomized placebo-controlled dose-ranging trials and one overnight sampling study, all in healthy adults, show CJC-1295 raises growth hormone and IGF-1 for days after a single injection. The largest enrolled a few dozen volunteers, measured hormone levels only, and lasted 49 days. No trial has measured muscle, fat, recovery or ageing outcomes, which are the uses it is sold for, so the grade is B on surrogate endpoints only.
The adult approval rested on REAL 1, a randomized, double-blind, placebo-controlled and active-controlled trial of 301 adults with growth hormone deficiency, and the pediatric approvals on randomized trials against daily somatropin, the most recent being the REAL8 basket trial across three indications. The question these trials answer is whether weekly somapacitan matches daily growth hormone, and they show it does.
FDA
Not approved
CJC-1295 is not approved by the FDA for any use and is sold as a research chemical. Its nominations for the compounding bulks list were withdrawn in September 2024, and in December 2024 the FDA's Pharmacy Compounding Advisory Committee voted against adding it, so it is not eligible for pharmacy compounding either.
FDA approved
Somapacitan is FDA-approved as Sogroya (Novo Nordisk), a once-weekly injection, for adults with growth hormone deficiency (August 2020), children aged 2.5 and older with growth hormone deficiency (2023), and, since February 27, 2026, children aged 2.5 and older with idiopathic short stature, short stature after being born small for gestational age, or growth failure from Noonan syndrome.
Sold for
CJC-1295 is sold as a long-acting growth-hormone booster for muscle gain, fat loss, sleep and recovery, usually paired with ipamorelin.
Somapacitan is the once-a-week growth hormone that replaces daily injections for children and adults who lack the hormone.
Studies say
Small trials in healthy volunteers confirm that it raises GH and IGF-1 for a week or more per injection, which is a real pharmacological effect measured on blood tests, but no study has shown it changes body composition or any health outcome.
Randomized trials show weekly somapacitan reduces body fat in adults with growth hormone deficiency as well as daily growth hormone does and produces equivalent growth in children, which supports an A for its approved uses.
Class
GHRH analog (secretagogue)
Long-acting GH analog
Route
Injection
Injection