The cholesterol on your lab report - LDL, HDL, triglycerides - has been the battleground of cardiovascular medicine for fifty years. But there's another fraction, remnant cholesterol, that accumulates in the blood of people with metabolic dysfunction and drives cardiovascular events even when LDL looks fine. Most doctors don't measure it. Fewer have tools to treat it.
Josh Lehrer built a company around that gap. Marea Therapeutics' lead program, MAR001, targets ANGPTL4 - a protein whose inhibition was flagged as cardioprotective through analysis of naturally occurring human genetic variants. The logic: if people who lose function of this gene are protected from heart disease, then blocking it with a drug might replicate that protection. The data has held.
The Doctor Who Stayed in the Lab
Lehrer trained as a cardiologist. Harvard for biochemical sciences, Cambridge for a Master of Philosophy in biological sciences, UCSF for his M.D., Stanford for his fellowship. He practiced as an attending physician at Stanford University Medical Center and the Palo Alto Veterans Affairs Health System. He is a Fellow of the American College of Cardiology - and still holds adjunct faculty status at Stanford's Division of Cardiology.
Most physicians who move into industry leave clinical medicine behind. Lehrer kept a foot in both worlds, and that dual perspective - seeing patients and building drugs - runs through every role he has held.
The Industry Track Record
Lehrer joined Genentech in 2009 and spent four years leading clinical development programs through proof of concept across multiple indications. He also touched business development and cardiovascular safety oversight - the unglamorous parts of drug development that determine whether a program lives or dies.
From Genentech, he moved to Global Blood Therapeutics as Vice President of Clinical Development, eventually rising to Chief Medical Officer. There, he oversaw the clinical work that led to the FDA approval of Oxbryta (voxelotor) - a first-in-class oral therapy for sickle cell disease that marked one of the most significant advances in that disease in decades. Getting a drug through the FDA is an exercise in precision and persistence. Lehrer had done it.
In April 2020, he became President and CEO of Graphite Bio, a gene-editing company that had set its sights on single-gene disorders. He led the company through a challenging period that included both scientific ambition and the difficult realities of early-stage gene therapy development. He stepped down in September 2023.
Building Marea from the Inside
A month after leaving Graphite Bio, Lehrer walked into Third Rock Ventures' incubation engine and became CEO of what would become Marea Therapeutics. The company had no public identity, no public name, and a science thesis centered on human genetics and cardiometabolic disease. Lehrer didn't wait for the press release to start building.
By June 2024, Marea went public with $190 million in combined Series A and Series B financing. The Series A came from Third Rock; the Series B was led by Sofinnova Investments and co-led by Forbion, Perceptive Xontogeny Venture Fund, and venBio, with additional participation from Alpha Wave Global, Omega Funds, Surveyor Capital (a Citadel affiliate), and Third Rock as a returning investor.
That funding round wasn't just capital - it was a bet on the ANGPTL4 hypothesis, on the genetic validation behind it, and on the team Lehrer had assembled.
The Clinical Evidence
Marea's Phase 2a results for MAR001 landed in May 2025, presented at the 93rd European Atherosclerosis Society Congress. The numbers: approximately 53% placebo-adjusted mean reductions in remnant cholesterol and triglycerides at 12 weeks. In the subgroup with baseline triglycerides above 200 mg/dL, the reductions reached 66% for remnant cholesterol and 64% for triglycerides. No serious adverse events. No deaths.
The data was published in The Lancet in May 2025 - the kind of peer-reviewed validation that separates press releases from science. The Phase 2b study, TYDAL-TIMI 78, is now underway in collaboration with the TIMI Study Group at Harvard Medical School, with topline results expected mid-2026.
Meanwhile, MAR002 - an allosteric growth hormone receptor antibody targeting acromegaly - completed Phase 1 with a 52% peak IGF-1 suppression at the highest dose tested. A Phase 2/3 registrational study is expected to begin mid-2026.
The Genetics Thesis
Lehrer's approach at Marea isn't just about chemistry. It's about starting with human genetics - identifying variants that nature has already tested in populations - and then engineering drugs that mimic those protective effects. The ANGPTL4 program emerged because loss-of-function variants in the ANGPTL4 gene are associated with lower cardiovascular risk in large epidemiological studies. The MAR002 program follows the same logic for growth hormone biology.
This methodology - human genetics first, drug development second - has become a signature approach in modern biotech. Lehrer is building an entire company around it, with an emerging siRNA platform expected to nominate additional development candidates in 2026.
Beyond Marea
In April 2026, Fulcrum Therapeutics appointed Lehrer to its Board of Directors as a Class III independent director, joining the Science and Technology Committee. His term runs through 2028. It's a signal of standing in the biotech community - when you've taken multiple programs into the clinic, driven an FDA approval, and published in The Lancet, boards come calling.
Lehrer presented Marea at the 44th Annual J.P. Morgan Healthcare Conference in January 2026, the industry's most closely watched annual gathering. He also presented at the Precision Medicine World Conference in 2022 and has spoken at educational symposia on rare and cardiovascular disease.
The mid-2026 readout of TYDAL-TIMI 78 will be closely watched. Remnant cholesterol is a real problem with no approved solution. If Phase 2b holds what Phase 2a suggested, the conversation around cardiovascular risk management will need updating - and Lehrer will have been mid-stride the whole time.