Updated May 2026 · ClinicalTrials.gov

RECRUITINGPhase 1INTERVENTIONAL

Phase 1 Study Evaluating the Safety and PK of ADU-1805 in Advanced Solid Tumors

An Open-Label, Multicenter, Multi-arm Phase 1 Study Evaluating the Safety and Pharmacokinetics of ADU-1805 in Adults With Advanced Solid Tumors

Phase 1 Study Evaluating the Safety and PK of ADU-1805 in Advanced Solid Tumors (NCT05856981) is a Phase 1 interventional studying Solid Tumor, Adult and Metastatic Solid Tumor, sponsored by Sairopa B.v.. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

What Stage of Research Is This?

Phase 1 trials test a new treatment for the first time in humans, focusing on safety, dosing, and how the body processes the drug. For Solid Tumor, Adult, a Phase 1 study typically enrolls a small number of participants — often healthy volunteers or patients who have exhausted standard treatment options. Phase 1 results determine whether a treatment moves into larger Phase 2 efficacy studies.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 130 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Solid Tumor, Adult subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.

Who May Be Eligible (Plain English)

Who May Qualify: - Male or female aged ≥18 years - Signed and dated willing to sign a consent form form - Measurable disease according to RECIST (Safety Expansion only) - You should be able to carry out daily activities with 0 level of ability (ECOG 0) or 1 - Adequate organ and marrow function - Escalation Phase: Histologically and/or cytologically confirmed diagnosis of metastatic or unresectable solid tumors that are refractory to standard therapy or for which no standard therapy exists - Expansion Phase: histologically and/or cytologically confirmed diagnosis of advanced PD-(L)1-naïve MSS colorectal cancer (CRC), PD-1 relapsed/refractory patients with either advanced MSS endometrial cancer (EC), renal cell carcinoma (RCC) or non-small cell lung cancer (NSCLC) patients, and that have measurable disease according to RECIST Who Should NOT Join This Trial: - Escalation Phase: Patients that suffer from melanoma, brain tumors, glioblastoma, sarcoma and pancreatic ductal adenocarcinoma (PDAC) - Expansion Phase: - \> 3 lines of prior systemic treatments - MSS colorectal cancer (CRC): liver metastasis present - Pregnancy or breast-feeding - Prior treatment with or receipt of: - biological agents, including monoclonal antibodies and immunotherapies, within 28 days prior to the first dose of ADU-1805 - chemotherapy, targeted small molecule therapy, hormonal therapy or radiation therapy within 21 days prior to the first dose of ADU-1805 and within 42 days for nitrosoureas and mitomycin C. - anti-SIRPα or anti-CD47-directed therapy - systemic chronic steroid therapy or immunosuppressive therapy within 14 days prior to the first dose of ADU-1805 - other investigational new drug or investigational device within 28 days prior to the first dose of ADU-1805 - vaccine containing live virus within 28 prior to the first dose of ADU-1805 - Active untreated brain metastases - Active infection requiring systemic therapy ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: * Male or female aged ≥18 years * Signed and dated informed consent form * Measurable disease according to RECIST (Safety Expansion only) * ECOG Performance status of 0 or 1 * Adequate organ and marrow function * Escalation Phase: Histologically and/or cytologically confirmed diagnosis of metastatic or unresectable solid tumors that are refractory to standard therapy or for which no standard therapy exists * Expansion Phase: histologically and/or cytologically confirmed diagnosis of advanced PD-(L)1-naïve MSS colorectal cancer (CRC), PD-1 relapsed/refractory patients with either advanced MSS endometrial cancer (EC), renal cell carcinoma (RCC) or non-small cell lung cancer (NSCLC) patients, and that have measurable disease according to RECIST Exclusion Criteria: * Escalation Phase: Patients that suffer from melanoma, brain tumors, glioblastoma, sarcoma and pancreatic ductal adenocarcinoma (PDAC) * Expansion Phase: * \> 3 lines of prior systemic treatments * MSS colorectal cancer (CRC): liver metastasis present * Pregnancy or breast-feeding * Prior treatment with or receipt of: * biological agents, including monoclonal antibodies and immunotherapies, within 28 days prior to the first dose of ADU-1805 * chemotherapy, targeted small molecule therapy, hormonal therapy or radiation therapy within 21 days prior to the first dose of ADU-1805 and within 42 days for nitrosoureas and mitomycin C. * anti-SIRPα or anti-CD47-directed therapy * systemic chronic steroid therapy or immunosuppressive therapy within 14 days prior to the first dose of ADU-1805 * other investigational new drug or investigational device within 28 days prior to the first dose of ADU-1805 * vaccine containing live virus within 28 prior to the first dose of ADU-1805 * Active untreated brain metastases * Active infection requiring systemic therapy * Impaired cardiac function or clinically significant cardiac disease * Current Grade \>2 toxicity related to prior anti-cancer therapy * History of drug-induced severe immune-related adverse reaction * Prior severe hypersensitivity to other monoclonal antibodies or ADU-1805 excipients * Major surgery within defined period * Diagnosis or positive test of HIV, hepatitis B, hepatitis C, or active tuberculosis * Allogenic tissue/solid organ transplant * Any intercurrent illness that is life-threatening or of such clinical significance that it would interfere with the patient's safety or ability to participate in the study

Treatments Being Tested

DRUG

ADU-1805

anti-SIRPα monoclonal antibody

DRUG

Pembrolizumab

Keytruda

Locations (7)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Henry Ford Cancer Institute

Detroit, Michigan, United States

Washington University Medical Campus

St Louis, Missouri, United States

Gabrail Cancer & Research Center

Canton, Ohio, United States

Virginia Cancer Specialists

Fairfax, Virginia, United States

Grand Hopital de Charleroi (GHdC) - Hopital Notre Dame

Charleroi, Belgium

Hosp 12 de Octubre

Madrid, Spain

Hospital General Universitario Gergorio Maranon

Madrid, Spain

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05856981), the sponsor (Sairopa B.v.), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05856981 clinical trial studying?

This first-in-human, open-label, multicenter, multi-arm dose-escalation study is designed to evaluate the safety, PK, and PD of ADU-1805, an anti- SIRPα monoclonal antibody, as monotherapy and in combination with pembrolizumab (anti-PD-1 antibody). The full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.

Who can participate in NCT05856981?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05856981?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05856981. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05856981. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.