Longeveron

Longeveron is a clinical-stage biotechnology company developing cellular therapies for age-related and life-threatening conditions. Their lead candidate product is laromestrocel (Lomecel-B™), which is culture-expanded mesenchymal stem cells (MSCs) sourced from young healthy adult bone marrow donors. Their thesis is that by promoting tissue repair, organ maintenance, and immune system function, these cells will be safe and effective therapies for some of the most challenging diseases and syndromes of aging.

The company has announced positive initial results from five clinical trials of laromestrocel across three indications:  Phase I and II in neurodegenerative aging of the Alzheimer’s type (AD), Phase I and II in age-related frailty, and Phase I in hypoplastic left heart syndrome (HLHS), a rare pediatric disease in which the left side of the heart is severely underdeveloped and incapable of delivering blood all across the body.

Longeveron’s corporate headquarters and GMP manufacturing facilities are located in Miami, Florida. In addition, the company acts as sponsor to what it calls a Treatment Registry Trial with two private partner clinics under local authority in The Bahamas, where patients can purchase laromestrocel at their own expense for one of four indications: frailty, mild cognitive impairment (MCI), AD and related dementias, and osteoarthritis. Even in The Bahamas, laromestrocel remains an investigational therapy.

In August 2025, Longeveron announced that it had closed an IPO worth up to $17.5 million.

Alzheimer’s Disease
In October 2023, Longeveron announced that laromestrocel had met its primary endpoint of safety in the Phase IIa CLEAR MIND trial (NCT05233774). The trial randomized subjects with ‘mild’ AD to receive placebo or one of three ascending doses of laromestrocel. There was one Serious Adverse Event (SAE) reported in each laromestrocel-treated group, versus none on placebo, but the Data and Safety Monitoring Board (DSMB) did not raise any safety issues. There were no cases of amyloid-related imaging abnormalities (ARIA), hypersensitivity, or notable changes in laboratory tests or electrocardiogram (EKG).

In addition, both the low-dose and the pooled laromestrocel groups improved their Composite Alzheimer’s Disease Score (CADS) scores from baseline to week 3, and a trend toward slower declines compared to placebo subjects. They also reported trends toward slowing of left hippocampal volume loss and slower worsening of their ADAS-cog13 and CDR-S ADCS-ADL relative to placebo, though findings were not consistent across all dose groups.

In June 2024, the company announced that FDA had granted laromestrocel regenerative medicine advanced therapy (RMAT) status for the treatment of mild AD, and shortly thereafter that it had granted them Fast Track designation for this indication.

Aging Frailty
In August 2021, Longeveron announced the results of a Phase IIb randomized, blinded (it is not clear if it was double-blinded) placebo-controlled trial of laromestrocel in patients with aging frailty, testing three ascending dose regimens versus placebo. In the primary analysis of the primary efficacy endpoint, subjects who received the highest three doses of laromestrocel experienced a statistically significant increase in the six-minute walk test (6MWT) at day 180 compared to the placebo group, whereas the placebo and lowest-dose laromestrocel groups showed no significant changes. However, after adjusting for multiple comparisons, only a trend toward improvement remained among patients that received the highest dose. Conversely, a prespecified secondary analysis of the primary endpoint:esablished a dose-response relationship in treated groups. Laromestrocel had no significant effect on any of the multiple secondary and exploratory endpoints.

In November 2021, it was announced that a sponsored clinical research agreement with the National Center for Geriatrics and Gerontology (NCGG) and Juntendo University Hospital in Japan had been reached for a Phase 2 trial to test for safety and efficacy in older and frail subjects.

Hypoplastic Left Heart Syndrome (HLHS)
Hypoplastic left heart syndrome (HLHS) is a rare pediatric disease in which the left side of the heart is severely underdeveloped and incapable of delivering blood all across the body. Newborns will present with poor feeding or cyanosis (purple skin) that does not respond to supplemental oxygen, followed by respiratory distress and in some cases cardiogenic shock and eventual death.

In January 2023, Longeveron-affiliated scientists reported the Phase I ELPIS I safety trial of laromestrocel treatment in ten HLHS patients following a standard reconstructive procedure. There were no major adverse cardiac events (MACE), all patients survived to the one-year mark, and none required a heart transplant. The investigators contrast these uncontrolled results with the historical experience of 10% of HLHS patients suffering right ventricular failure and requiring a heart transplantation or dying, “with less than half of the children having transplant-free survival to 15 years of age.” Treated patients also had normal growth curves, and cardiac MRI suggested that their tricuspid regurgitant fraction improved at 6 and 12 months post-transplant.

In October 2024, Longeveron announced the results of a multi-year follow-on study to the ELPIS I participants. All ten laromestrocel-treated HLHS patients had survived for five years, with none requiring a heart transplant. For comparison, historical controls from the Single Ventricle Reconstruction Trial had suffered a 17% mortality rate and a 5.2% heart transplantation rate.

In June 2025, Longeveron announced that FDA had granted laromestrocel Orphan Drug designation, Fast Track designation, and Rare Pediatric Disease designation for HLHS, and the company had completed enrollment of the pivotal Phase IIb ELPIS II clinical trial to test laromestrocel in HLHS patients. The company anticipates having topline trial results available in Q3 of 2026, after the final 12-month followup.

Pediatric Dilated Cardiomyopathy
In July 2025, Longeveron announced that FDA had approved an IND application to move laromestrocel directly into a Phase II pivotal registration study in pediatric dilated cardiomyopathy (DCM) patients. The company anticipates that the trial will begin in the first half of 2026.