---
title: "Parabilis Medicines, Clinical-Stage Biopharma Targeting Undruggable Proteins, Files for Nasdaq IPO"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/286966794.md"
description: "Parabilis Medicines has filed for an IPO on the Nasdaq under the ticker 'PBLS'. The funds will support the late-stage development of its lead drug, zolucatetide, aimed at treating various cancers. The company focuses on developing Helicons, peptides targeting undruggable proteins, and has strategic partnerships, including one with Regeneron. Currently, Parabilis is pre-revenue, with significant operational losses reported for 2025."
datetime: "2026-05-19T20:58:24.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/286966794.md)
  - [en](https://longbridge.com/en/news/286966794.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/286966794.md)
---

# Parabilis Medicines, Clinical-Stage Biopharma Targeting Undruggable Proteins, Files for Nasdaq IPO

Parabilis Medicines, a clinical-stage biopharmaceutical company developing drugs for historically undruggable protein targets, has filed for an initial public offering. The company plans to list on the Nasdaq Global Market under the ticker “PBLS.” Proceeds will support late-stage development of its lead asset zolucatetide, expansion into additional indications, advancement of its pipeline, and platform investment.

**Business Description**

Parabilis Medicines is a clinical-stage biopharmaceutical company developing Helicons—stabilized helical peptides engineered to penetrate cells and bind flat protein–protein interaction surfaces long considered undruggable. Its lead candidate, zolucatetide, is designed to directly inhibit the β‑catenin:TCF interaction at the critical downstream node of the Wnt/β‑catenin pathway. The drug is being evaluated across multiple solid tumors with pathway activation, including desmoid tumors (lead indication), familial adenomatous polyposis (FAP), hepatocellular carcinoma (HCC), additional rare Wnt/β‑catenin‑driven tumors, and in combinations for colorectal cancer (CRC).

Beyond zolucatetide, Parabilis is advancing two preclinical Helicon degrader programs in prostate cancer: an ERG degrader targeting fusion‑driven disease and an allosteric ARON degrader intended to overcome resistance associated with AR amplification and ligand‑binding domain mutations while remaining combinable with existing AR antagonists. The company’s proprietary discovery engine integrates AI‑ and physics‑based modeling with high‑throughput peptide synthesis and multiplexed screening, generating large proprietary datasets to accelerate design, optimization, and manufacturability of complex synthetic molecules.

**Market Overview**

-   **Total addressable market**: Wnt/β‑catenin pathway alterations occur in over 10% of all cancers; desmoid tumors ~11,000 actively managed U.S. patients; FAP ~34,000 U.S. patients; HCC ~38,000 new U.S. cases and 700,000–800,000 globally; CRC ~2 million new cases globally per year.
-   **Market growth**: Increasing oncology incidence globally with growing focus on molecularly defined and tumor‑agnostic therapies.
-   **Market position**: Parabilis reports first direct inhibition of the β‑catenin:TCF interaction via Helicon peptides, aiming at historically undruggable intracellular targets.
-   **Key competitors**: γ‑secretase inhibitors for desmoid tumors, including nirogacestat (Ogsiveo) and varegacestat; off‑label TKIs (e.g., sorafenib, imatinib, pazopanib); chemotherapy and immuno‑oncology regimens in CRC and HCC.
-   **Industry trends**: Rising interest in protein–protein interaction modulation, targeted protein degradation, AI‑driven discovery platforms, and potential tumor‑agnostic regulatory pathways.

**Operational Metrics**

-   **Customers**: Pre‑commercial; no paying customers reported.
-   **Locations**: Headquarters and labs in Cambridge, Massachusetts (~122,000 sq. ft.).
-   **Geographic presence**: U.S. clinical sites to date; planning international expansion in future phases.
-   **Partnerships**: Strategic collaboration with Regeneron (upfront $50 million and an expected $75 million concurrent equity investment) to explore Antibody‑Helicon Conjugates.
-   **Clinical activity**: \>150 patients dosed with zolucatetide across indications.
-   **Desmoid tumor cohort**: 38 patients treated; among 19 evaluable with ≥2 post‑baseline scans, 74% ORR per RECIST 1.1; disease control observed in all 25 patients with at least one post‑baseline scan.
-   **FAP signal**: Early duodenal polyp burden reductions observed in initial patients; dedicated cohort planned.
-   **HCC signal**: Confirmed partial response in a heavily pre‑treated CTNNB1‑mutant patient; HCC‑specific cohort enrolling.
-   **Employees**: 145 full‑time employees and 31 full‑time consultants (as of April 1, 2026).
-   **Manufacturing**: Outsourced to CDMOs; processes developed for scale‑up; self‑administered injectable formulation in development.
-   **Intellectual property**: At least 17 patent families across platform and programs.

**Financials Highlights**

-   **Revenue (current)**: None (pre-revenue)
-   **Operating income**: Loss from operations of $(152.1) million for 2025
-   **Net income**: Net loss of $(145.9) million for 2025

**Management**

-   **Mathai Mammen, M.D., Ph.D.**, Chairman, Chief Executive Officer and President - Former Global Head of R&D at Johnson & Johnson and SVP at Merck; co‑founded Theravance; leadership across discovery/development of 19 approved medicines.
-   **Fawzi Benzaghou, M.D.**, Chief Medical Officer - Former SVP and Global Head of Oncology R&D at Ipsen; contributed to multiple oncology approvals including Cabometyx and Onivyde.
-   **Helen Ho, Ph.D.**, Chief Business and Strategy Officer - Former CBO at Blueprint Medicines; prior corporate development roles at Agios and TCR2; Ph.D. in Cell Biology from Yale.
-   **Thomas Kotarakos**, Chief Financial Officer - Former SVP Finance at Codiak BioSciences and Corporate Controller at Seres Therapeutics; CPA.
-   **Rohin Mhatre, Ph.D.**, Chief Technical Operations Officer - Former SVP, Pharmaceutical Development, Engineering & Technology at Biogen; extensive CMC leadership.

**IPO Structure**

-   **Issuer**: Parabilis Medicines, Inc.
-   **Filing date**: May 19, 2026
-   **Proposed ticker**: PBLS
-   **Exchange**: Nasdaq Global Market
-   **Lead underwriters**: Leerink Partners; BofA Securities; Evercore ISI; Guggenheim Securities; LifeSci Capital
-   **Use of proceeds**: Fund Phase 3 development of zolucatetide in desmoid tumors, expand trials across FAP, HCC and other Wnt/β‑catenin-driven tumors, advance ERG and ARON degraders and β‑catenin degraders toward Phase 1, continue Helicon platform evolution, and for general corporate purposes.

Original SEC Filing: Parabilis Medicines, Inc. - S-1 - May. 19, 2026

**Disclaimer**

This is an AI-powered summary. It may contain inaccuracies. Consider verifying important information with the source. Please note this summary is solely based on documents filed with the SEC.

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