Curium Presents First Dosimetry, PK Data for Lu‑177 Zadavotide; Supports 7.4 GBq

Curium announced that dosimetry and pharmacokinetic data from a 26‑patient nonrandomized substudy of its pivotal Phase 3 ECLIPSE trial support administering 7.4 GBq of lutetium‑177 zadavotide guraxetan per treatment for up to six cycles, and the company amended the trial to raise the maximum from four to six doses. The data were presented in a poster at ASCO GU 2026 in San Francisco, where Curium outlined biodistribution and organ absorbed dose assessments for patients with metastatic castration‑resistant prostate cancer (mCRPC) enrolled in ECLIPSE, NCT05204927.

Curium described the substudy as focused on organ biodistribution and absorbed radiation dose, noting the study design as the nonrandomized PK/dosimetry substudy (n=26) conducted as part of the ECLIPSE trial to evaluate the biodistribution and radiation absorbed dose of Lu‑177 zadavotide guraxetan to organs of interest. ECLIPSE is testing the proprietary formulation of 177Lu‑PSMA‑I&T in patients who progressed on prior androgen receptor pathway inhibitor therapy.

In its summary statement Curium said, “Dosimetry data from the Phase 3 ECLIPSE substudy demonstrated favorable organ radiation absorbed doses supporting administration of 7.4 GBq for up to six cycles.” Curium’s chief medical officer Sakir Mutevelic, MD, framed the findings more fully: “These data represent the first published dosimetry data for our investigational formulation of Lu‑177 zadavotide guraxetan, with projected mean cumulative renal doses remaining low for a six‑cycle treatment regimen, thus supporting a protocol amendment to increase from a maximum of four doses to six in the ECLIPSE trial.”

Curium did not publish absolute organ dose numbers or detailed PK parameters in its press materials, and the available excerpts include no mGy or mSv values, no numeric half‑life or clearance figures, and no adverse event tables or efficacy outcomes for the 26 participants. Those gaps mean the ASCO GU poster PDF or abstract will be needed to review organ‑by‑organ dosimetry tables, numeric PK metrics, demographics of the substudy cohort, and any safety listings that underpinned the protocol amendment.

The company placed the ECLIPSE update alongside program expansion: Curium, with PeptiDream Inc. and PDRadiopharma Inc., reported dosing the first patient in a registrational Phase 2 177Lu‑PSMA‑I&T study in Japan on February 4, 2026, and Curium’s news archive references IND acceptance by China’s regulator on December 23, 2025 and a separate first commercial dosing of PYLCLARI® in Poland on December 23, 2025. Curium also amplified the ASCO GU message on LinkedIn with cancer care hashtags and reported social engagement metrics including 113 likes and 8 comments.

Independent commentary framed the practical impact: Jack Patterson of The Patterson Perspective wrote that “The ability to safely administer more cycles is a critical step forward. For patients, it could translate into a greater cumulative dose of radiation delivered directly to tumors, potentially leading to deeper and more durable responses against the cancer.” Curium reiterated its regulatory and commercial intent in Mutevelic’s closing line: “We will continue to evaluate the ECLIPSE clinical trial data with the goal of bringing this potential therapy to market for those living with mCRPC. This reinforces our long‑term vision to treat 80 percent of cancers within the next 10‑15 years.”