Replacing and improving kidneys is moving from the lab to human trials.

▌ TODAY’S CHALLENGE: Can you tell a healthy kidney from a damaged one? A photo test waits at the very bottom. Read to the end and test your eye.

Welcome to EverLife Capital. Read today’s issue to be in the know on kidney advancements.

“The best way to predict the future is to invent it.” Alan Kay

In a German study of 12,381 adults aged 35 to 74, kidney filtration fell by about 1 mL/min/1.73 m² a year over five years (Scientific Reports, 2021). That is an average, so it does not predict your own path. In the CDC's 2020 survey, self-reported kidney disease was 1.1% at ages 18 to 44, 3.1% at 45 to 64, and 7.1% at 65 and older (CDC).

Together, your two kidneys hold about two million tiny filters called nephrons, which clean about 150 quarts of blood a day and turn 1 to 2 quarts into urine (NIDDK). Kidneys also make hormones that help control blood pressure, make red blood cells, and keep bones strong (NIDDK). The companies below try to restore filtering cells, help filter cells make protective proteins, or replace the organ.

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Rilparencel, an investigational cell therapy made from the patient's own cells, is in Phase 3 for advanced kidney disease with type 2 diabetes. The company says the stage 3b/4 CKD with diabetes group it targets includes over one million people in the U.S. Chief Technical Officer Kenneth Locke, appointed in June 2026, previously led manufacturing, quality and regulatory work at Carisma Therapeutics on first-in-human cell therapy programs. Cash, cash equivalents and marketable securities were $181.6M at June 30, 2026, of which $74.9M was cash and cash equivalents, and the company says that supports operations into mid-2027 (Q2 report). Market data (Oct 23, 2026 close): PROK $1.41, market cap about $422M. Why it matters: it is already in Phase 3, and whether it preserves kidney function enough for approval is still being tested. Next (company estimates): enrollment of the roughly 320-patient accelerated-approval efficacy analysis is complete, full enrollment of about 470 is due 2H 2026, kidney-function results are expected Q2 2027, and the confirmatory results 2H 2029.

Its UKidney, from a pig with 10 gene edits, is in the EXPAND trial, with the first transplant announced in November 2025 (announcement). Six human genes were added and four pig genes removed so the human immune system rejects it less. About 815,000 U.S. patients have kidney failure, more than 555,000 are on dialysis and about 90,000 are on the transplant waiting list (company release, citing USRDS and the American Kidney Fund). Unlike a human donor kidney, supply would not depend on donors, but only about 22,000 deceased-donor kidney transplants happened in 2024 and the trial must still show the pig kidney lasts and is safe. CEO Martine Rothblatt founded United Therapeutics in 1996 and earlier helped create satellite radio company Sirius, now SiriusXM. The company reported $3.8B in cash and marketable investments in its Q2 2026 investor deck. Market data (Oct 22, 2026 close): UTHR $584.79, market cap about $25.1B. Why it matters: its established drug business provides resources to support development. Next: review results from the initial six-patient cohort and seek agreement with the FDA on expansion.

As of its September 3, 2026 update, five patients had received its pig kidney under expanded access, and one had gone over nine months without dialysis, which the company calls a record (update). Its pig kidney has three pig sugar antigens removed, seven human genes added and pig retroviruses inactivated, to reduce rejection and infection risk. The company cites more than 800,000 Americans with kidney failure, about 28,000 U.S. kidney transplants in 2024 and a 60% five-year mortality rate linked to dialysis. Versus dialysis it aims to restore filtering without a machine, and versus a human transplant it is not limited by donor supply, but long-term durability is unproven. CEO Mike Curtis, PhD, was president and head of R&D at Cadent Therapeutics and earlier led three products from discovery to first-in-human or Phase 2 at Catabasis. Scientific founders George Church and Luhan Yang are behind a 2017 Science paper from the team that reported the first pigs with inactivated PERV retroviruses. It raised a $191M Series D in September 2024. Backers: Leaps by Bayer, Eisai Innovation and NATCO Pharma (Series D release); dialysis companies DaVita and Fresenius Medical Care Ventures. Why it matters: it is a private developer with reported human expanded-access experience. Its engineered pig cells have also been used by collaborator PorMedTec to produce donor pigs in Japan (joint announcement). Next: the company expects to start its FDA-cleared, 33-patient RESTORE trial in Q1 2027.

▌ DID YOU KNOW? About 9 in 10 adults with chronic kidney disease (87%) do not know they have it (CDC). That is why early testing matters.

Its drug RN-014 for polycystic kidney disease is a small molecule found with an iPS-cell disease model and has finished a Phase 2a trial. About 140,000 people in the U.S. are diagnosed with ADPKD, the most common inherited form (HCPLive, 2018). The approved drug tolvaptan slowed the yearly eGFR decline by about 1.0 mL/min/1.73 m² in the TEMPO 3:4 trial. RN-032, its separate cell-regeneration program, is moving into nonclinical studies. The July 2026 financing brought the J-KISS round to ¥1.7 billion (about $10.8M), with a Taiwanese investor leading the second close (announcement). Backers: Mitsui Chemicals and Asahi Kasei. Could it help healthy people with normal kidney aging? Unknown. RN-014 has only been studied in people with polycystic kidney disease, and no study shows it slows ordinary age-related decline, so that idea is a hypothesis, not evidence. Could it help healthy people with normal kidney aging? Unknown. RN-014 has only been studied in people with polycystic kidney disease, and no study shows it slows ordinary age-related decline, so that idea is a hypothesis, not evidence. Why it matters: it pursues both a drug and a regeneration program, with the iPS technology coming from Kyoto University's CiRA. Next: Phase 2a data analysis (no date), and a Series C planned from autumn 2026 onward.

Its PS-002 is in a Phase 1/2 trial for IgA nephropathy. A harmless virus (AAV) carries the gene for complement factor I into podocytes so they make the protein locally and calm damaging immune activity in the filters. About 1 in 10 U.S. kidney biopsies show IgA nephropathy, and about 1 in 5 patients develop kidney failure within 10 years (NIDDK). Today's care is blood pressure and protein-lowering drugs, with steroids or other immunosuppressants for some, and there is no cure, so this tests a one-time gene therapy. CEO Haseeb Ahmad, since March 2025, was previously president of Novartis Europe and led Novartis Gene Therapies, including Zolgensma. Founder Prof. Moin Saleem of the University of Bristol started the podocyte gene therapy program in 2014 and originated the UK RaDaR rare renal disease registry. It tests whether a single administration can make kidney filter cells produce complement factor I, a protein that helps control damaging immune activity. It raised £80M (about $107M) in October 2024. Backers: Syncona, Sofinnova, Forbion, Gilde Healthcare and British Patient Capital. Why it matters: it is being tested as a single-administration gene therapy delivered to one cell type. Next: dose escalation and expansion in up to 32 participants. PS-003 for Alport syndrome was presented at ASN Kidney Week on October 24, and the findings were preclinical (abstract).

▌ BAD KIDNEY JOKE BREAK: Why did the kidney break up with the liver? It said, “You are too toxic.”

Trestle is preclinical and won a $1M KidneyX prize. Trestle licensed kidney bioprinting technology from Harvard to build kidney tissue. More than 808,000 Americans live with kidney failure, and Medicare spent $52.3B on it in 2021 (USRDS). Humacyte founder Laura Niklason, MD, PhD, won FDA approval of Symvess, its engineered vessel, in December 2024. Humacyte had $80.3M in cash and restricted cash at June 30, 2026, and raised about $57.5M gross in a June 2026 offering. In March 2025 the two signed a research and material transfer agreement to explore a bioengineered kidney, with no financial terms disclosed. Partner: Humacyte works with Fresenius Medical Care on engineered vessels, which does not mean Fresenius backs the Trestle kidney project (Humacyte filing). Market data (Oct 20, 2026): HUMA $0.41, market cap about $113M. Why it matters: it is an early attempt to build kidney tissue that carries its own blood supply. Next: no dated milestones announced.

It develops gene-edited pigs for transplant. Its pigs are bred with three genes knocked out, the triple knockout. About 90,000 people are on the U.S. kidney waiting list, and 27,660 adult kidney transplants were done in 2024 (SRTR). It follows the same organ-replacement route as United Therapeutics and eGenesis, with a three-gene knockout versus United Therapeutics' 10 edits. Scientific founder Joseph Tector, MD, PhD, discovered the triple knockout pig in his lab and heads xenotransplantation at the Miami Transplant Institute. In September 2024 it announced a plan for a first-in-human kidney trial in early 2026, pending FDA approval. I could not confirm that it started, and the latest company news I found (April 2025) describes preclinical work. Partner: Tonix Pharmaceuticals (announced April 2025) to study its TNX-1500 antibody with Makana’s pig organs and cells in preclinical work.

In March 2025, Xijing Hospital reported a pig-kidney transplant in a 69-year-old woman doing well about three weeks after surgery (AP). This is not a current patient-status report, and the supplier was not named.

Built on Yale research, it develops one-time gene therapies for polycystic kidney disease. It aims to use gene therapy to reactivate the polycystin genes, an approach that shrank cysts in mouse work from co-founder Stefan Somlo's Yale lab. About 140,000 people in the U.S. are diagnosed with ADPKD (HCPLive, 2018). The approved drug tolvaptan slows decline by about 1.0 mL/min/1.73 m² a year, while Estuary is developing a gene therapy. Co-founder Xavier Anguela was formerly VP of gene therapy at Eli Lilly. It announced $103M in committed financing: a $93M Series A led by RA Capital, plus an earlier $10M seed (company announcement). Backers: Biogen New Ventures, with GV also participating. Why it matters: it targets the cause of the disease and has strong backing while still preclinical. Next: the company anticipates starting human studies of EST-201 in 2027 and EST-101 in 2028.

It raises cloned donor pigs from gene-edited cells provided by eGenesis, and raised about ¥510M (about $3.2M) in February 2025 to scale production (Meiji University). Backers: Sekine and the JGC Mirai Innovation Fund. Founder Hiroshi Nagashima, a Meiji University professor, leads the institute known for cloned pig production. Why it matters: it aims to supply pig kidneys in a country with a severe donor shortage. Next: Japan's first pig-to-human kidney trials, as early as 2028 (Nippon.com).

Active recruitment: Purespring's PS-002 says it is recruiting on its patient page. I could not retrieve current registry status for the others. Registry listings: ProKidney's PROACT 1, Purespring's PS-002, and United Therapeutics' EXPAND. Past guidance put EXPAND at ages 55 to 70 on hemodialysis for at least six months. Planned start: eGenesis RESTORE, Q1 2027, for waitlisted patients aged 50 to 70. Age and diagnosis alone do not establish eligibility, so check each registry and talk to your doctor first.

In that German study, albuminuria (protein in the urine) and higher systolic blood pressure were the strongest predictors of faster decline, so ask your doctor to check both. In the ARIC study, the highest adherence to a healthy plant-based diet went with 14% lower relative risk of kidney disease than the lowest adherence, over a median 24 years (Healio). This is an association, not proof. NIDDK says long-term ibuprofen or naproxen can damage kidneys, and ACE inhibitors or ARBs, when prescribed, may slow loss of function (NIDDK).

The first business case is one organ, one disease, one approval, and kidney failure is where the options are narrowest. Late-stage kidney trials are costly: ProKidney used $82.1M of operating cash in the first half of 2026. If kidney repair works, the same tools could later extend to other organs. That step is unproven.

Which one is damaged? Look at the photo of two kidneys below. Do they look healthy to you?

Answer: Both are damaged. These are kidneys with polycystic kidney disease, filled with fluid-filled cysts. A healthy kidney is smooth and bean shaped. Photo: CDC Public Health Image Library (public domain).

Educational research, not investment advice.