Warren Banta, MD
NPI 1861695678ActiveIndividual· Internal Medicine, Hematology & Oncology· Los Angeles, CA
Internal Medicine, Hematology & Oncology (MD) with Austin J Ma MD A Professional Corporation, practicing in Los Angeles, California. Their prescriptions cost Medicare Part D more than their services did: $11,595,378 for 2,921 claims, against $16,022 paid for services in 2024. Novartis Pharmaceuticals Corporation was the largest of 39 companies reporting payments in 2025, $6,397 in all, mostly food and beverage. Lists Eisenhower Medical Center as a hospital affiliation.
Overview
| NPI | 1861695678 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | Yes |
| NPI issued | Jun 8, 2007 |
| Last updated in NPPES | Jan 6, 2010 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Hematology & Oncology Primary | 207RH0003X | A88514 | CA |
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 - Hematology/Oncology (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 40 |
|---|---|
| Services billed | 1,457 across 33 procedure codes |
| Paid by Medicare | $16,022 |
Part D prescriptions in 2024
| Prescriptions (claims) | 2,921 · 4,169 30-day fills |
|---|---|
| Patients | 507 |
| Total drug cost | $11,595,378 |
| Generic share | 61% of claims |
Education and affiliations
| Graduation year | 2002 |
|---|---|
| Medicare specialty | Hematology/Oncology |
| Telehealth | Offers telehealth |
Medical group
- Austin J Ma MD A Professional CorporationOxnard, CA · 11 clinicians
Hospital affiliation
- Eisenhower Medical CenterRancho Mirage, CA
Industry payments (Open Payments)
- 2025$6,397 · 247 payments from 39 companies
- 2024$6,351 · 246 payments from 43 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Novartis Pharmaceuticals Corporation | $1,371 | 35 |
| Janssen Biotech, Inc. | $655.77 | 24 |
| Pfizer Inc. | $618.83 | 24 |
| Bayer Healthcare Pharmaceuticals Inc. | $414.15 | 21 |
| Astrazeneca Pharmaceuticals LP | $336.54 | 16 |
What the 2025 payments were for
- Food and Beverage$5,297 · 234 payments
- Long term medical supply or device loan$999.96 · 12 payments
- Education$99.99 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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