ARPA-H COSMOS Initiative Seeks to Test Whether Space Can Accelerate Regenerative Drug Development

COSMOS Solicitation Overview

COSMOS is structured as a two-phase effort. Phase I lasts 27 months and is designed to establish and validate the MPS platform, execute terrestrial and LEO twin studies, and determine whether the aging rate in space materially exceeds the aging rate on Earth for the selected organ and age groups. Only tissue types and donor ages that demonstrate a sufficiently compelling TARIS:TAROE relationship will advance to Phase II.

During Phase I, performers must execute both terrestrial and flight comparison studies using donor tissues from three required adult age brackets: approximately 30, 45, and 65 years old, each within a two-year range. The LEO twin study requires a minimum of 384 single-donor MPS units, divided equally between flight and terrestrial comparators. The two planned LEO flights are tentatively scheduled for months 19 and 23 after contract award, with tissue preservation after two and four weeks in flight. All LEO experiments must operate fully autonomously, without human interaction from launch through splashdown.

The Government will separately select commercial service providers to provide flight hardware, experimental housing, launch logistics, power, imaging, sample preservation, and microfluidic support. Selected performer teams must coordinate closely with these providers to engineer their MPS platforms for flight. The solicitation requires the MPS and associated microfluidic support design to be locked no later than month 10 after contract award.

Phase II is contingent on Phase I results. Teams that proceed will use the organ and age brackets showing the strongest evidence that TARIS exceeds TAROE to establish MPS based disease models and conduct targeted regenerative-therapy screening in LEO. Phase II includes two additional tentative launches and calls for drug screening against validated controls and candidate therapeutics relevant to the selected tissue and aging-associated biological pathways.

Commercialization is a core program requirement rather than a downstream aspiration. By the end of Phase I, each team must establish a signed contractual partnership with at least one Fortune 100 biopharmaceutical company. That partner must have relevant therapeutic assets or a drug library for the selected organ area, including at least three drug candidates that are approved for age-related disease in the target tissue or target aging-relevant pathways in clinical testing. Teams must also explain how any demonstrated acceleration in aging could translate into downstream patient value, including potential reductions in therapeutic development time and cost.

Technical Objectives and Capability Areas

COSMOS is designed to measure the Tissue Aging Rate in Space (TARIS) against the Tissue Aging Rate on Earth (TAROE). ARPA-H intends to determine, with experimental evidence, whether microgravity in LEO produces detectable aging or age like changes in human tissues over weeks rather than years.

The program focuses on four tissues tied to major age-related disease burden:

• Brain, including neurodegenerative conditions such as Alzheimer’s disease, Parkinson’s disease, and other dementias.
• Heart, with relevance to cardiovascular disease, vascular dysfunction, and related pathologies.
• Uterus, addressing poorly understood age-associated reproductive and gynecologic conditions.
• Kidney, with relevance to chronic kidney disease and related long term organ dysfunction.

Each proposer may select only one of these organ areas. The proposed MPS must model the organ’s relevant structure, function, cellular composition, and age related biology. Performers may use primary human cells, induced pluripotent stem cells, or healthy-donor tissue samples, although use of iPSCs requires organ-specific justification. At least 75% of experimental units must be MPS, while organoids may comprise a limited portion of the experimental cohort as a contingency or complementary model.

The required technical approach is demanding. Strong teams will need demonstrated capabilities across:

• Microphysiological systems, organ-on-chip design, and microfluidics engineering.
• Human primary cell, tissue, and/or iPSC-derived organ models.
• Organ-specific physiology, pathology, and age-related disease biology.
• Autonomous laboratory operations and payload integration for spaceflight.
• Multi-omics data generation and quantitative analysis.
• Computational biology, machine learning, and in-silico aging model development.
• Biopharmaceutical drug screening strategy and translational research.
• Regulatory planning, intellectual property strategy, research security, and BIOSECURE Act compliance.

ARPA-H requires each team to develop a preflight in-silico model of aging for its selected organ using existing and open source data. That model must provide the baseline for terrestrial data, guide subsequent TARIS/TAROE analysis, and be refined using data from the LEO twin studies. The resulting model is expected to help identify prospective commercial biopharmaceutical partners and relevant drug libraries for potential Phase II work.

Key Dates & Submission Timeline

All deadlines are in Eastern Time.

• October 1, 2026, 5:00 PM ET: Questions and Answers submission deadline.
• October 7, 2026, 2:00 PM ET: Full proposals due.
• October 7, 2026, 2:00 PM ET: ISO closing date.

ARPA-H requires submission through the ARPA-H Solution Submission Portal. Proposers must register before submitting, and ARPA-H cautions that portal registration can take several business days. Delays caused solely by late registration may not excuse a late proposal. Questions should be submitted through the ARPA-H question portal or directed to [email protected].

Funding Overview

ARPA-H anticipates making multiple Other Transaction (OT) agreements under COSMOS. The solicitation does not specify total program funding or target award values. Award decisions will be based on the proposals deemed most advantageous to the Government, considering scientific and technical merit, performer capabilities and relevant experience, and cost reasonableness.

The agency may select all, some, one, or none of the submitted proposals, and may negotiate awards that fund only portions of a proposal. ARPA-H also reserves the right to structure awards with phases or options, enabling continued funding decisions to be tied to technical performance, schedule execution, commercial-partnership progress, and achievement of program milestones.

Building the LEO Biopharma Platform

COSMOS is an ambitious attempt to turn microgravity from a scientific curiosity into a usable commercial-development variable. The central question is straightforward but high stakes: if human tissue models in LEO exhibit reproducible, meaningful age-related changes much faster than matched terrestrial controls, drug developers could gain a faster way to model disease, test regenerative interventions, and prioritize therapeutic candidates. If the hypothesis does not hold, COSMOS is equally designed to provide the data needed to establish that conclusion.

For prospective performers, this is not a conventional organ on chip proposal and it is not a conventional spaceflight project. A credible solution must integrate tissue engineering, organ-specific biology, autonomous hardware compatibility, multi-omics, computational modeling, program management, and a real commercial biopharma path. The short proposal window makes early decisions critical: select one organ where the team has defensible depth, validate donor access and production-scale assumptions, identify the gaps that require partners, and determine whether a Fortune 100 biopharmaceutical relationship can be credibly established within the Phase I timeline.