Obicetrapib for Heterozygous Familial Hypercholesterolemia: BROOKLYN Trial Correction

A newly published author correction in Nature Medicine reaffirms the findings of the BROOKLYN randomized clinical trial, which evaluated the efficacy and safety of obicetrapib in patients with heterozygous familial hypercholesterolemia (HeFH). The correction, issued on April 17, 2026, does not alter the study’s primary conclusions but clarifies minor statistical details in the original report. The trial remains a significant contribution to understanding how obicetrapib, a cholesteryl ester transfer protein (CETP) inhibitor, affects lipid profiles in a high-risk genetic population.

The BROOKLYN trial, a phase 3 randomized, double-blind, placebo-controlled study, enrolled adults with HeFH who were already on maximally tolerated statin therapy. Participants were randomly assigned to receive either obicetrapib or placebo in addition to their background lipid-lowering regimen. The primary endpoint was the percent change in low-density lipoprotein cholesterol (LDL-C) from baseline to week 24. According to the corrected findings, obicetrapib led to a statistically significant reduction in LDL-C compared to placebo, with a mean difference of approximately 30% after 24 weeks of treatment.

Secondary endpoints included changes in other lipid and lipoprotein markers. Obicetrapib treatment was associated with increases in high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I, consistent with the mechanism of CETP inhibition. Levels of lipoprotein(a) [Lp(a)] showed a modest but significant decrease, a finding of potential clinical relevance given Lp(a)’s role as an independent risk factor for atherosclerotic cardiovascular disease. Triglyceride levels remained largely unchanged across treatment groups.

Safety monitoring throughout the trial revealed that obicetrapib was generally well tolerated. The most frequently reported adverse events were mild to moderate in severity and included nasopharyngitis, headache, and musculoskeletal pain. Rates of serious adverse events were low and balanced between the obicetrapib and placebo groups. Notably, there were no significant increases in liver enzyme abnormalities, muscle-related symptoms suggestive of myopathy, or renal dysfunction attributable to the drug. Blood pressure and glycemic parameters also showed no clinically meaningful deviations from baseline.

The authors emphasize that while obicetrapib demonstrated robust lipid-modifying effects in this genetically defined population, the BROOKLYN trial was not powered to assess clinical outcomes such as myocardial infarction, stroke, or cardiovascular mortality. As such, the reduction in LDL-C and other lipid markers, while biologically plausible as a predictor of reduced cardiovascular risk, requires confirmation in larger, long-term outcomes trials. The correction notes that ongoing studies are evaluating obicetrapib’s impact on atherosclerotic plaque progression and hard cardiovascular endpoints in broader populations, including those with established atherosclerotic cardiovascular disease.

Heterozygous familial hypercholesterolemia affects approximately 1 in 250 individuals worldwide and is characterized by markedly elevated LDL-C levels from birth, leading to premature atherosclerotic cardiovascular disease if untreated. Despite advances in lipid-lowering therapy, many patients with HeFH fail to achieve LDL-C targets on statins alone, necessitating additional pharmacologic options. Obicetrapib represents a novel mechanism of action that complements existing therapies by enhancing reverse cholesterol transport and modulating lipoprotein metabolism.

The BROOKLYN trial contributes to a growing body of evidence supporting the role of CETP inhibitors in managing dyslipidemia, particularly in high-risk groups. Earlier generations of CETP inhibitors failed to demonstrate cardiovascular benefit despite improving lipid profiles, often due to off-target effects or lack of efficacy in outcomes trials. Obicetrapib, designed to be more selective and potent, has shown promise in early-phase studies for its favorable lipid-altering profile without the adverse signals seen with prior agents in the class.

Experts in preventive cardiology and lipidology note that while genetic therapies and novel siRNA-based treatments are emerging for HeFH, oral agents like obicetrapib offer a practical and accessible option for long-term management, especially in resource-limited settings. However, they caution that LDL-C lowering alone does not equate to proven clinical benefit, and regulatory approval will depend on demonstration of improved cardiovascular outcomes in pivotal trials.

The authors disclose that the BROOKLYN trial was sponsored by the pharmaceutical company developing obicetrapib. Academic medical centers and lipid clinics across North America and Europe participated in participant recruitment and follow-up. The correction was initiated following a routine internal review that identified minor inconsistencies in the reporting of confidence intervals for secondary endpoints, which have now been resolved in the updated version of the article.

As research into obicetrapib continues, the scientific and clinical communities await results from ongoing phase 3 outcomes trials. Until such data are available, the use of obicetrapib in clinical practice remains investigational. For patients with HeFH, current guidelines recommend maximizing tolerated statin therapy, adding ezetimibe if LDL-C goals are not met, and considering PCSK9 inhibitors or other approved agents based on individual risk profile and treatment response.