Dear Acromegaly Community,

We are writing to share some exciting updates from Crinetics’ Phase 3 PATHFNDR-1 study. We just issued a press release where you can learn more, but we are pleased to report that:


  • The study met its primary endpoint with 83% of participants on paltusotine maintaining an IGF-1 ≤1.0 xULN vs. 4% on placebo after 36 weeks of treatment (p<0.0001)
  • Mean IGF-1 levels were maintained on paltusotine vs an increase on placebo after switching from injected depot standard of care (p<0.0001).
  • All other secondary endpoints were met including change from baseline in Acromegaly Symptoms Diary (ASD) score (p=0.02) and the proportion of participants who achieved a GH level of <1.0ng/mL (p=0.0003)
  • Paltusotine was well-tolerated with no severe or serious adverse events


We hope that you share our excitement about what these results could mean for the acromegaly community!  Crinetics is dedicated to the development of much-needed therapies for people with endocrine conditions.

We hope that the compelling data from the PATHFNDR-1 study of our investigational compound, paltusotine, can bring optimism to the other communities we seek to serve.

Lastly, we want to convey our deep gratitude to the extraordinary people with acromegaly who helped to make this study a success by sharing their unmet needs for treatment and by participating in our studies. Below, please find a list of answers to some questions you may have:


What is the PATHFNDR-1 study?

  • PATHFNDR-1 is one of two ongoing, placebo-controlled Phase 3 studies of the investigational compound, paltusotine
  • PATHFNDR-1 looked at paltusotine in participants with acromegaly who switched from standard of care injectables. These topline results are based on 36 weeks of data and showed the investigational compound provided reliable, consistent and durable IGF-1 control


Why is this study important?

  • Treatment for acromegaly aims to lower certain hormones in the body – IGF-1 and GH – and also reduce symptoms of acromegaly
  • Surgery is the usual first-line treatment for acromegaly. When symptoms continue after surgical treatment, medical treatment in the form of an injectable is often used
  • To our knowledge, paltusotine is the first oral, once-daily selectively targeted somatostatin receptor type 2 (SST2) agonist being evaluated for the treatment of acromegaly
  • For patients looking for an alternative to injections, if approved, paltusotine has the potential to reduce the burden of acromegaly treatment


Can you share more background on paltusotine?

  • Paltusotine is an oral once-daily medication that is a new class of medicine that selectively targets receptors in the pituitary to reduce growth hormone secretion and can replace depot injections
  • Based on phase 3 results, paltusotine has the potential to help acromegaly patients control their IGF levels and symptoms


What is the difference between PATHFNDR-1 and 2 and why are there two studies?

Based on guidance from the U.S. Food and Drug Administration (FDA), the FDA specifies two distinct patient populations in acromegaly:

  • Patients whose disease is controlled on medical therapy. This is the subject of our PATHFNDR-1 study
  • Patients who are initiating treatment. This is subject of our PATHFNDR-2 study.  In the PATHFNDR-2 study the enrollment is for participants who have not received therapy (treatment-naïve), recently untreated, or agree to washout of their current injectables


What comes next?

  • We are working to complete the full analysis of the PATHFNDR-1 results and plan to present additional data at an upcoming scientific meeting.
  • Our second Phase 3 study, PATHFNDR-2, is fully enrolled, and we anticipate topline data in Q1 2024
  • We hope to file with the FDA in 2024 and make the drug available to patients if it is approved, in 2025


If you or your healthcare provider have questions for a member of our team, please contact [email protected].

We look forward to sharing more information as it is publicly available.



The Crinetics Team