Tomas Gerald Neilan, MD
NPI 1437285145ActiveIndividual· Internal Medicine, Cardiovascular Disease· Boston, MA
Internal Medicine, Cardiovascular Disease (MD) with Massachusetts General Physicians Organization Inc, practicing in Boston, Massachusetts. Their prescriptions cost Medicare Part D more than their services did: $401,905 for 1,892 claims, against $65,157 paid for services in 2024. Merck Sharp & Dohme LLC was the largest of 7 companies reporting payments in 2025, $79,414 in all, mostly consulting fees. Lists Brigham and Women's Hospital and 4 other hospitals as hospital affiliations.
Overview
| NPI | 1437285145 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Feb 26, 2007 |
| Last updated in NPPES | Jan 3, 2026 |
| Certified by provider | Jan 3, 2026 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Cardiovascular Disease Primary | 207RC0000X | 234637 | MA |
| Internal Medicine | 207R00000X | 234637 | MA |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Oct 9, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 10, 2026 | No match | — |
| New York OMIG · Nov 10, 2026 | No match | — |
| Ohio Medicaid · Nov 10, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 10, 2026 | No match | — |
| Washington HCA · Nov 10, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Cardiovascular Disease (Cardiology) (MA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 999 |
|---|---|
| Services billed | 1,918 across 12 procedure codes |
| Paid by Medicare | $65,157 |
Part D prescriptions in 2024
| Prescriptions (claims) | 1,892 · 5,011 30-day fills |
|---|---|
| Patients | 274 |
| Total drug cost | $401,905 |
| Generic share | 83% of claims |
Education and affiliations
| Graduation year | 1996 |
|---|---|
| Medicare specialty | Cardiovascular Disease (Cardiology) |
| Secondary specialties | Internal Medicine |
| Telehealth | Offers telehealth |
Medical group
- Massachusetts General Physicians Organization IncBoston, MA · 3,558 clinicians
Hospital affiliations
- Brigham and Women's HospitalBoston, MA
- Massachusetts General HospitalBoston, MA
- Newton-Wellesley HospitalNewton, MA
- North Shore Medical Center -Salem, MA
- Winchester HospitalWinchester, MA
Industry payments (Open Payments)
- 2025$79,414 · 29 payments from 7 companies
- 2024$19,151 · 10 payments from 4 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Merck Sharp & Dohme LLC | $40,640 | 4 |
| Glaxosmithkline, LLC. | $9,640 | 3 |
| E.R. Squibb & Sons, L.L.C. | $8,671 | 3 |
| Genentech, Inc. | $8,061 | 8 |
| Gilead Sciences, Inc. | $5,353 | 3 |
What the 2025 payments were for
- Consulting Fee$78,323 · 28 payments
- Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program$1,092 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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