Automated Physician Outreach
to Recruit Patients
for Clinical Trials

An automated system that identifies physicians who treat patients matching a study's inclusion criteria, contacts them through multiple channels, and generates patient referrals directly into the trial site's enrollment pipeline. It replaces informal word-of-mouth recruiting with a scalable, data-driven workflow that runs continuously across every active study, using the CMS NPPES NPI Registry as its physician data source.

The National Provider Identifier Registry is a public CMS database of 1.5M+ licensed US physicians. Each record includes taxonomy code (specialty), practice address, and contact info. The NPPES API lets you pull every physician of a specific specialty within a geographic area without scraping or purchasing a list — enabling a site to find every relevant physician by therapeutic area taxonomy code filtered by radius, in seconds, for free.

For obesity and metabolic disease trials: 207RE0101X (Endocrinology), 207RB0002X (Obesity Medicine), 207R00000X (Internal Medicine). For rheumatology: 207RR0500X, 207RI0008X. For cardiovascular: 207RC0000X, 207RI0011X (Interventional Cardiology). For CNS and psychiatry: 2084N0400X (Neurology), 2084P0800X (Psychiatry). For oncology: 207RX0202X (Medical Oncology), 207RH0000X (Hematology). The system maps any therapeutic area to its relevant taxonomy codes and queries all in a single pull.

For clinical trial physician outreach, a well-constructed sequence targeting by specialty and indication achieves 5 to 12% reply rate — significantly higher than the generic B2B cold email average of 1 to 5%. The relevance is high: the physician is being contacted about patients they already treat who may qualify for a study near their practice.

Cold email: 5–12% reply rate. LinkedIn connections: 30–45% accept rate. Physical postcards to the practice address: 12–18% response rate per USPS data for healthcare professionals. Social media retargeting builds name recognition before the email arrives. The most effective approach runs all channels from a single physician record — one NPI data pull, five simultaneous touchpoints.

Hunter.io uses email pattern discovery, MX record lookup, and SMTP verification to confirm whether an email address exists and will deliver. For physician outreach, Hunter is queried with the physician's name and practice domain and returns a confidence score. Verified addresses (85%+ confidence) are queued for outreach. This keeps bounce rate under 2%, protecting sender domain reputation and maintaining inbox placement rates.

When a physician replies with a patient referral, an AI layer reviews the patient details against the study's inclusion and exclusion criteria before the coordinator sees the message. Patients who clearly do not qualify are flagged automatically. Patients who may qualify are routed to the coordinator with a pre-screening summary. Qualified referrals write directly to the CTMS via API, creating the patient record without any data entry.

Pre-built integrations are available for Veeva SiteVault, CRIO, RealTime eClinical, and Clinical Conductor. Custom CTMS API integrations are available for proprietary site platforms. Every qualified referral creates a patient record via API — referral source, pre-screening status, and physician contact all logged automatically with full attribution for sponsor reporting.