Association of Lonafarnib Treatment vs No Treatment With Mortality Rate in Patients With Hutchinson-Gilford Progeria Syndrome
Leslie B Gordon, Heather Shappell, Joe Massaro, Ralph B D'Agostino Sr, Joan Brazier, Susan E Campbell, Monica E Kleinman, Mark W Kieran, Leslie B Gordon, Heather Shappell, Joe Massaro, Ralph B D'Agostino Sr, Joan Brazier, Susan E Campbell, Monica E Kleinman, Mark W Kieran
Abstract
Importance: Hutchinson-Gilford progeria syndrome (HGPS) is an extremely rare fatal premature aging disease. There is no approved treatment.
Objective: To evaluate the association of monotherapy using the protein farnesyltransferase inhibitor lonafarnib with mortality rate in children with HGPS.
Design, setting, and participants: Cohort study comparing contemporaneous (birth date ≥1991) untreated patients with HGPS matched with treated patients by age, sex, and continent of residency using conditional Cox proportional hazards regression. Treatment cohorts included patients from 2 single-group, single-site clinical trials (ProLon1 [n = 27; completed] and ProLon2 [n = 36; ongoing]). Untreated patients originated from a separate natural history study (n = 103). The cutoff date for patient follow-up was January 1, 2018.
Exposure: Treated patients received oral lonafarnib (150 mg/m2) twice daily. Untreated patients received no clinical trial medications.
Main outcomes and measures: The primary outcome was mortality. The primary analysis compared treated patients from the first lonafarnib trial with matched untreated patients. A secondary analysis compared the combined cohorts from both lonafarnib trials with matched untreated patients.
Results: Among untreated and treated patients (n = 258) from 6 continents, 123 (47.7%) were female; 141 (54.7%) had a known genotype, of which 125 (88.7%) were classic (c.1824C>T in LMNA). When identified (n = 73), the primary cause of death was heart failure (79.4%). The median treatment duration was 2.2 years. Median age at start of follow-up was 8.4 (interquartile range [IQR], 4.8-9.5) years in the first trial cohort and 6.5 (IQR, 3.7-9.0) years in the combined cohort. There was 1 death (3.7%) among 27 patients in the first trial group and there were 9 deaths (33.3%) among 27 patients in the matched untreated group. Treatment was associated with a lower mortality rate (hazard ratio, 0.12; 95% CI, 0.01-0.93; P = .04). In the combined cohort, there were 4 deaths (6.3%) among 63 patients in the treated group and 17 deaths (27.0%) among 63 patients in the matched untreated group (hazard ratio, 0.23; 95% CI, 0.06-0.90; P = .04).
Conclusions and relevance: Among patients with HGPS, lonafarnib monotherapy, compared with no treatment, was associated with a lower mortality rate after 2.2 years of follow-up. Study interpretation is limited by its observational design.
Conflict of interest statement
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosures of Conflicts of Interest. Drs Gordon, Kleinman, and Kieran report receiving grants and nonfinancial support from the National Institutes of Health and The Progeria Research Foundation. Dr Gordon is the parent of a child who participated in the study. Drs Massaro and D’Agostino and Mss Brazier and Campbell report receiving grants from The Progeria Research Foundation. No other disclosures were reported.
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Source: PubMed