Calico Life Sciences Announces U.S. FDA Orphan Drug Designation for Investigational Treatment of Autosomal Dominant Polycystic Kidney Disease

SAN FRANCISCO, Nov. 5, 2025 /PRNewswire/ -- Calico Life Sciences LLC (Calico), a biotechnology organization focused on aging and age-related diseases and founded by Alphabet Inc. and Arthur D. Levinson, today announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) to ABBV-CLS-628, an investigational therapy for the treatment of Autosomal Dominant Polycystic Kidney Disease (ADPKD). ABBV-CLS-628, an anti-PAPP-A monoclonal antibody, was developed by Calico in collaboration with AbbVie Inc. The therapy was recently granted Fast Track Designation by the FDA and is currently in a Phase 2 clinical trial evaluating its safety and efficacy in patients with ADPKD.

"We are pleased that ABBV-CLS-628 has received both Fast Track and Orphan Drug designations, underscoring the urgent unmet need facing the ADPKD community," said Arthur D. Levinson, Ph.D., CEO of Calico. "People living with this disease face a high risk of rapid disease progression and we will continue to advance this program with the goal of improving the treatment trajectory for patients."

ADPKD is the most common inherited kidney disease worldwide.¹ Characterized by the development and growth of fluid-filled cysts in both kidneys, the progressive disease leads to kidney failure in more than 50% of patients by age 60. At that stage, dialysis or a transplant are the only treatment options.²

The ODD was created under the Orphan Drug Act, a law passed by Congress in 1983 that incentivizes the development of drugs to treat rare diseases. Rare disease is defined as affecting fewer than 200,000 individuals in the United States. The ODD request requires evidence demonstrating potential efficacy or "promise to treat" using nonclinical and/or clinical data. Benefits include tax credits for qualified clinical trials, protocol assistance, a seven-year period of market exclusivity, and exemption from user fees if the drug receives approval.³

About ABBV-CLS-628
ABBV-CLS-628, an investigational human monoclonal antibody designed to inhibit PAPP-A activity, is being evaluated for the treatment of ADPKD. ABBV-CLS-628 has completed a Phase 1 study in healthy volunteers (ACTRN12622001550796) in which it was shown to be safe and well tolerated with no significant adverse events reported to be associated with the drug.

The ongoing Phase 2 study (NCT06902558) is now enrolling across approximately 95 sites globally. Participants receive intravenous ABBV-CLS-628 or placebo every 4 weeks for 92 weeks, with safety follow-up for up to 15 weeks. This study is designed to evaluate the safety, tolerability, and potential efficacy of ABBV-CLS-628 in slowing disease progression in ADPKD.

About Calico
Calico (Calico Life Sciences LLC) is an Alphabet-founded research and development company whose mission is to harness advanced technologies and model systems to increase our understanding of the biology that controls human aging. Calico will use that knowledge to devise interventions that enable people to lead longer and healthier lives. To learn more about Calico, visit www.calicolabs.com. Follow @calico on LinkedIn, X, and YouTube.

References
1 – NIH NIDDK (2025, November 3)
2 – National Kidney Foundation (2025, November 3)
3 – Designating an Orphan Product | FDA (2025, November 3)

SOURCE Calico Life Sciences LLC