Eli Lilly unveiled new data Monday that it says raises the prospect of a one-and-done cholesterol-lowering treatment for certain patients at high cardiovascular risk.In updated interim results from the Phase Ib Heart-2 study, presented at the European Atherosclerosis Society (EAS) congress, the company reported that its in vivo PCSK9 base-editing therapy VERVE-102 reduced levels of the target protein by up to 88% and cut LDL cholesterol (LDL-C) by as much as 62%. In some participants, the effects have lasted as long as 18 months after a single infusion.The therapy is being developed for patients with heterozygous familial hypercholesterolaemia (HeFH) or premature coronary artery disease (CAD) who remain at high cardiovascular risk despite maximally tolerated oral lipid-lowering treatments.In an earlier interim readout last year, the drug's developer, Verve Therapeutics — then still independent — reported encouraging LDL-C and PCSK9 reductions alongside an apparently improved safety profile versus its original candidate, VERVE-101, which had been paused over side effects tied to the lipid nanoparticle (LNP) delivery system. Those earlier results helped set the stage for Lilly's eventual takeover of Verve a few months later for $1.3 billion, marking the pharma's formal entry into the PCSK9 space (see – Vital Signs: Eli Lilly double-dips in cardiometabolic disease with Verve takeout)."One of the biggest challenges in cardiovascular prevention remains long-term adherence to chronic therapy," Scott Vafai, Lilly vice president and chief medical officer at Verve, told FirstWord in an email. "When it comes to LDL-C, the key isn't only how much you lower it, but how long you keep it low. VERVE-102 is designed to potentially address this need."The therapy works by replicating naturally occurring loss-of-function mutations in PCSK9 that are associated with lifelong low LDL-C and reduced coronary risk. It uses an mRNA encoding an adenine base editor and guide RNA delivered via LNPs to the liver. It also uses a newer GalNAc-LNP delivery system to avoid the safety issues seen with VERVE-101.The latest Heart-2 update is based on 35 participants, with data showing dose-dependent reductions in circulating PCSK9 ranging from 51% to 88% across six dose cohorts (0.3 mg/kg to 1.0 mg/kg). LDL-C dropped by 9% to 62%, though the 0.7 mg/kg dose was an exception, with a smaller LDL-C reduction than nearby doses."In a small early-phase study, some variability between intermediate cohorts can occur," Vafai explained. "As such, we think it is most appropriate to look at the totality of the PCSK9 and LDL-C datasets rather than any single dose group in isolation. Importantly, at 1.0 mg/kg, VERVE-102 produced robust reductions in both PCSK9 and LDL-C."The durability questionMore follow-up is needed to fully understand how long the treatment's effects will last, and all participants will continue to be monitored over the long term. Still, Vafai said Lilly sees signs that the benefit could prove lasting, including durable results in non-human primates and evidence in humans that the edit has persisted beyond the typical 200- to 300-day lifespan of hepatocytes, suggesting the edit is carried forward as new cells form.Last year, Intellia Therapeutics also reported that a single dose of its in vivo CRISPR-based therapy nexiguran ziclumeran (nex-z; NTLA-2001), which inactivates the TTR gene in the liver, saw sustained effect through three years in patients with hereditary transthyretin amyloidosis with polyneuropathy. The therapy has been marred by safety concerns, however. The FDA hit pause on the programme last year after a patient in one of Intellia's trials experienced a severe liver toxicity after receiving nex-z and died. The FDA lifted the clinical hold earlier this year.Lilly said safety findings for VERVE-102 were consistent with the earlier readout. The therapy was generally well tolerated across all dose levels, with no treatment-related serious adverse events, no dose-limiting toxicities, and no participant discontinuations. Reported side effects were mainly low-grade infusion-related reactions and fatigue.Lilly plans to begin enrolling the Phase II study of VERVE-102 by the end of this year.Looking ahead, Vafai said it is still "too early to speak to the long-term economics" of the VERVE-102, but "we do think there is a strong rationale for evaluating the potential economic value of a one-time treatment in a disease area that today relies on lifelong, chronic therapy."In addition to the PCSK9 programme, Lilly said the Phase Ib PULSE-1 trial for VERVE-201, an investigational in vivo gene editing medicine that targets the ANGPTL3 gene, is ongoing.