STOPFOP Trial (saracatinib)

STOPFOP Trial (saracatinib)

FOP is caused by a mutation in the ACVR1 gene that results in excessive bone morphogenetic protein (BMP) signaling through a protein kinase called ALK2, which regulates cartilage and bone development. The FOP mutation increases BMP signaling, resulting in the formation of heterotopic bone.

Saracatinib, also known as AZD0530, is an investigational drug that was initially developed as a potential treatment for patients with cancer. Scientific research by the STOPFOP team has shown that saracatinib blocks the activity of the FOP receptor, ALK2. In preclinical (animal) studies, saracatinib demonstrated potency for the drug to suppress of heterotopic ossification (HO) or bone formation in FOP animal models.

Saracatinib has been tested for safety and efficacy in humans with cancer and healthy volunteers. Over 600 people have used the drug, which means researchers are familiar with the effects and safety profile of the drug. The drug is taken orally, as a once-daily dose.

About the Clinical Trial

The aim of the STOPFOP trial is to see if the investigative drug saracatinib could be used to treat FOP. This study is supported by a grant from the European Commission’s Innovative Medicine Initiative. The STOPFOP team will aim to recruit 20 adults with the classical FOP genetic mutation into a clinical trial to test the safety and efficacy of saracatinib. Each patient’s participation in the study will last 1.5 years, with a 6-month randomized placebo-controlled trial (RCT) period followed by a 12-month open-label extended treatment period. This ensures that all participants will receive the investigational drug during the trial. Assessment measures will include CT scan, PET-scan and Patient Reported Outcome Measures (PROMs).

Eligibility Criteria Icon
Eligibility Criteria*
  • AGE: ≥ 18, ≤65
  • DISEASE ACTIVITY: No restrictions
Study Design Icon
Study Design*
  • STUDY TYPE: Interventional
Status Icon

Phase 2,
Phase 2: Studies that further test safety and begin to test the effectiveness of the drug, often at a variety of doses.  
Active, Not Recruiting

Study Sponsor Icon
Study Sponsor

Amsterdam University Medical Center, funded by the European Commission’s Innovative Medicine Initiative

Therapy Approach Icon
Therapy Approach

Kinase Inhibitor


*For the complete list of eligibility criteria and details on this study, visit and use NCT04307953.

Participating Clinical Sites


Amsterdam University Medical Center
Amsterdam, The Netherlands, 1081 HV
Contact: Tea Chan [email protected]
Contact: Bernard Smilde, MD
Contact: Marelise Eekhoff, MD, PhD
Coordinating Principal Investigator: Marelise Eekhoff, MD, PhD

Royal National Orthopaedic Hospital, Brockely Hill
Stanmore, United Kingdom, HA7 4LP
Contact: Richard Keen, MD, PhD
Contact: Jackie Vinton
Principal Investigator: Richard Keen, MD

Klinikum Garmisch-Partenkirchen
Garmisch-Partenkirchen, Germany, 82467
Contact: Clemens Stockklausner, MD, PhD
Principal Investigator: Clemens Stockklausner, MD

For additional information on the STOPFOP program: visit or have your doctor contact one the STOPFOP physicians.

The IFOPA does not endorse nor recommend specific clinical trials. Please speak with your doctor if you are interested in participating in a clinical trial.

Make a Difference

Donate Connect Fundraise
Already a Member? Sign In

Sign Up for FOP Connection, Our Monthly eNewsletter