Cancer clinical trials represent the largest single category of recruiting studies worldwide, encompassing everything from early-phase safety studies of novel oncology drugs to large Phase 3 comparisons against current standard-of-care chemotherapy regimens. The field has accelerated dramatically with the rise of immunotherapy, targeted therapies, and CAR-T cell treatments that have transformed outcomes for previously untreatable malignancies.
Trials include checkpoint inhibitors (PD-1/PD-L1 agents), KRAS inhibitors, ADC (antibody-drug conjugates), combination chemotherapy regimens, radiation protocols, and surgical technique comparisons. Many trials stratify by biomarker status (PD-L1 expression, TMB, MSI-H) to identify patients most likely to benefit.
The NCI, pharmaceutical sponsors, and academic cancer centers collectively fund thousands of oncology trials annually across every cancer type.
Frequently Asked Questions — cancer of unknown primary Clinical Trials
How many clinical trials are currently recruiting for cancer of unknown primary?
ClinicalMetric currently tracks 3 actively recruiting clinical trials for cancer of unknown primary, sourced in real time from ClinicalTrials.gov. The total number of registered studies—including those not yet enrolling or in active follow-up—is 3. Trial availability changes daily as new studies open enrollment and existing ones reach capacity.
What trial phases are available for cancer of unknown primary?
cancer of unknown primary research spans Phase 2 (1 trial). Phase 1 studies evaluate safety and dosing in small groups, Phase 2 studies assess preliminary efficacy in 100–300 participants, and Phase 3 trials compare the new treatment against the standard of care in 300–3,000+ patients. Phase 4 post-approval studies monitor long-term outcomes in real-world populations.
How do I find out if I qualify for a cancer of unknown primary clinical trial?
Eligibility criteria for cancer of unknown primary trials vary by study and typically specify age range, disease stage or severity, prior treatment history, and specific diagnostic or laboratory parameters. Each listing on ClinicalMetric links to the full protocol on ClinicalTrials.gov, where inclusion and exclusion criteria are documented. Contact the sponsoring site's research coordinator directly to confirm your eligibility—your treating physician or specialist can also help identify the most appropriate trial based on your medical history and current treatment status.
Top Sponsors
Erasmus Medical Center 1 trial
Instituto do Cancer do Estado de São Paulo 1 trial
The Christie NHS Foundation Trust 1 trial
Recruiting Clinical Trials
ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional.
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Last Reviewed: April 2026 ·
Data Methodology