1
|
Ayers KL, Glicksberg BS, Garfield AS, Longerich S, White JA, Yang P, Du L, Chittenden TW, Gulcher JR, Roy S, Fiedorek F, Gottesdiener K, Cohen S, North KE, Schadt EE, Li SD, Chen R, Van der Ploeg LHT. Melanocortin 4 Receptor Pathway Dysfunction in Obesity: Patient Stratification Aimed at MC4R Agonist Treatment. J Clin Endocrinol Metab 2018; 103:2601-2612. [PMID: 29726959 PMCID: PMC7263790 DOI: 10.1210/jc.2018-00258] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/27/2018] [Indexed: 01/03/2023]
Abstract
CONTEXT The hypothalamic melanocortin 4 receptor (MC4R) pathway serves a critical role in regulating body weight. Loss of function (LoF) mutations in the MC4R pathway, including mutations in the pro-opiomelanocortin (POMC), prohormone convertase 1 (PCSK1), leptin receptor (LEPR), or MC4R genes, have been shown to cause early-onset severe obesity. METHODS Through a comprehensive epidemiological analysis of known and predicted LoF variants in the POMC, PCSK1, and LEPR genes, we sought to estimate the number of US individuals with biallelic MC4R pathway LoF variants. RESULTS We predict ~650 α-melanocyte-stimulating hormone (MSH)/POMC, 8500 PCSK1, and 3600 LEPR homozygous and compound heterozygous individuals in the United States, cumulatively enumerating >12,800 MC4R pathway-deficient obese patients. Few of these variants have been genetically diagnosed to date. These estimates increase when we include a small subset of less rare variants: β-MSH/POMC,PCSK1 N221D, and a PCSK1 LoF variant (T640A). To further define the MC4R pathway and its potential impact on obesity, we tested associations between body mass index (BMI) and LoF mutation burden in the POMC, PCSK1, and LEPR genes in various populations. We show that the cumulative allele burden in individuals with two or more LoF alleles in one or more genes in the MC4R pathway are predisposed to a higher BMI than noncarriers or heterozygous LoF carriers with a defect in only one gene. CONCLUSIONS Our analysis represents a genetically rationalized study of the hypothalamic MC4R pathway aimed at genetic patient stratification to determine which obese subpopulations should be studied to elucidate MC4R agonist (e.g., setmelanotide) treatment responsiveness.
Collapse
Affiliation(s)
- Kristin L Ayers
- Department of Genetics and Genomic Sciences, Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York
- Sema4, Stamford, Connecticut
| | - Benjamin S Glicksberg
- Department of Genetics and Genomic Sciences, Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York
| | | | | | | | | | - Lei Du
- WuXiNextCode, Cambridge, Massachusetts
| | | | | | - Sophie Roy
- Rhythm Pharmaceuticals, Boston, Massachusetts
| | | | | | | | - Kari E North
- University of North Carolina, Chapel Hill, North Carolina
| | - Eric E Schadt
- Department of Genetics and Genomic Sciences, Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York
- Sema4, Stamford, Connecticut
| | - Shuyu D Li
- Department of Genetics and Genomic Sciences, Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York
- Sema4, Stamford, Connecticut
- Correspondence and Reprint Requests: Shuyu D. Li, PhD, or Rong Chen, PhD, Icahn School of Medicine at Mount Sinai, 1255 5th Avenue, New York, New York 10029. E-mail: or; or Lex H. T. Van der Ploeg, PhD, Rhythm Pharmaceuticals, 500 Boylston Street, Boston, Massachusetts 02116. E-mail:
| | - Rong Chen
- Department of Genetics and Genomic Sciences, Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York
- Sema4, Stamford, Connecticut
- Correspondence and Reprint Requests: Shuyu D. Li, PhD, or Rong Chen, PhD, Icahn School of Medicine at Mount Sinai, 1255 5th Avenue, New York, New York 10029. E-mail: or; or Lex H. T. Van der Ploeg, PhD, Rhythm Pharmaceuticals, 500 Boylston Street, Boston, Massachusetts 02116. E-mail:
| | - Lex H T Van der Ploeg
- Rhythm Pharmaceuticals, Boston, Massachusetts
- Correspondence and Reprint Requests: Shuyu D. Li, PhD, or Rong Chen, PhD, Icahn School of Medicine at Mount Sinai, 1255 5th Avenue, New York, New York 10029. E-mail: or; or Lex H. T. Van der Ploeg, PhD, Rhythm Pharmaceuticals, 500 Boylston Street, Boston, Massachusetts 02116. E-mail:
| |
Collapse
|
2
|
Granger CB, Vogel V, Cummings SR, Held P, Fiedorek F, Lawrence M, Neal B, Reidies H, Santarelli L, Schroyer R, Stockbridge NL, Feng Zhao. Do we need to adjudicate major clinical events? Clin Trials 2008; 5:56-60. [PMID: 18283081 DOI: 10.1177/1740774507087972] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The use of centralized systems to adjudicate clinical events is common in large clinical trials, in spite of relatively little published literature concerning the rationale and justification. The purpose of this manuscript is to review the reasons for central adjudication and to discuss whether trials could be simplified by limiting or streamlining the adjudication process. METHODS We reviewed the literature concerning central adjudication and documented the experience of adjudication in several clinical trials. Since definitions for nonfatal events are generally heterogeneous and subjective, one reason for a central process of adjudication is to assist in assuring systematic application of the definition used in the trial. In open-label trials, assuring that the adjudication is done blinded to treatment assignment may provide protection against differential misclassification. Regulatory authorities, including the FDA, derive confidence in the validity of results when central adjudication is performed. The clinical community has become accustomed to a certain amount of adjudication and may criticize trials that lack adjudication. LIMITATIONS It is difficult to document the value of adjudication in trials that have reported adjudicated and nonadjudicated event rates and related treatment effects. Making rationale decisions about when and how to adjudicate is hampered by the lack of published study of when and how central adjudication is helpful to improve the quality and validity of trials and at what cost. CONCLUSIONS Adjudication has not been shown to improve the ability to determine treatment effects. Thus, adjudication may be overly complex and overused in many large simple trials. The appropriate role of central adjudication - which trials, which outcomes, what methods - deserves scrutiny and further study.
Collapse
|