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Science-based information about the melanocortin-4 receptor pathway
Melanocortin-4 receptor pathway information
Find out more about the latest of our cutting-edge research available to the community
Congresses and meetings relevant to rare melanocortin-4 receptor pathway diseases throughout 2023
Access learning tools, educational resources and additional information about rare melanocortin-4 receptor pathway diseases
World Forum, The Hague, The Netherlands
European Society for Paediatric Endocrinology 2023
Rhythm-sponsored Promotional Satellite Symposium
Hyperphagia and early-onset, severe obesity: The role of precision medicine in the treatment of leptin melanocortin-4 receptor (MC4R) pathway diseases
Recording available now. Click here to watch.
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Welcome to path4HCPs
Here you can learn more about rare melanocortin-4 receptor (MC4R) pathway diseases, their diagnosis and management.
Rare MC4R pathway diseases can be caused by genetic variants within the pathway (part of the central melanocortin pathway). These changes can impair signalling in the pathway that controls hunger and can be a root cause of increased appetite and body weight.1
To accurately diagnose and care for those possibly living with a rare MC4R pathway disease, it is crucial to undertake a detailed observation of the patient and gain confirmation of any underlying genetic cause.
A proper understanding of a root cause of the disease allows for appropriate management and care of patients.1
Here you can find information about rare MC4R pathway diseases, including:
Bardet-Biedl syndrome

Bardet-Biedl syndrome (BBS) is a rare ciliopathy, resulting from genetic variants within the BBS family of genes. This heterogeneous genetic disease presents with a variety of symptoms that can evolve over time, including:2,3
- Cognitive impairment
- Early-onset, severe obesity
- Genital anomalies
- Hyperphagia
- Polydactyly
- Renal disease
- Visual impairments
Diagnosis of BBS is based on clinical findings; diagnosis confirmed by genetic testing.3
Pro-opiomelanocortin deficiency and leptin receptor deficiency

Pro-opiomelanocortin (POMC) and leptin receptor (LEPR) deficiencies are genetically identifiable rare MC4R pathway diseases (known as monogenic obesity). They are autosomal recessive inherited diseases caused by variants in the POMC or LEPR gene. Diagnosis of POMC and LEPR deficiency may be suspected based on clinical manifestations, such as hyperphagia and early-onset obesity, and is confirmed by genetic testing.2
Learn more about the cardinal symptoms of rare melanocortin-4 receptor pathway diseases
Dr Ashley Shoemaker, Vanderbilt University Medical Center and Dr Ilene Fennoy, New York-Presbyterian Hospital/Columbia University Medical Center explain more about the clinical presentation of the cardinal symptoms of rare MC4R pathway diseases, hyperphagia and early-onset severe obesity. Including key signs, symptoms and cues to look for during a consultation.
Latest videos


References:
- 1. .Yazdi F et al, Peerj, 2023;3;e856.
- 2. Huvenne H, et al. Obes Facts. 2016;9:158-73.
- 3. Forsythe et al., Orphanet Journal. 2023;18(12).