Isoken Koko, MD
NPI 1265465728ActiveIndividual· Internal Medicine, Hematology & Oncology· River Forest, IL
Internal Medicine, Hematology & Oncology (MD) with Insight Chicago Inc, practicing in River Forest, Illinois. Their prescriptions cost Medicare Part D more than their services did: $5,486,963 for 1,274 claims, against $56,890 paid for services in 2024. Seagen Inc. was the largest of 19 companies reporting payments in 2025, $1,574 in all, mostly food and beverage. Lists Insight Hospital and Medical Center Chicago and 4 other hospitals as hospital affiliations.
Overview
| NPI | 1265465728 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Jul 8, 2006 |
| Last updated in NPPES | Jan 23, 2017 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Hematology & Oncology Primary | 207RH0003X | 036100278 | IL |
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 (IL) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 270 |
|---|---|
| Services billed | 645 across 16 procedure codes |
| Paid by Medicare | $56,890 |
Part D prescriptions in 2024
| Prescriptions (claims) | 1,274 · 2,044 30-day fills |
|---|---|
| Patients | 217 |
| Total drug cost | $5,486,963 |
| Generic share | 63% of claims |
Education and affiliations
| Graduation year | 1984 |
|---|---|
| Medicare specialty | Hematology/Oncology |
| Secondary specialties | Internal Medicine |
Medical group
- Insight Chicago IncChicago, IL · 141 clinicians
Hospital affiliations
- Insight Hospital and Medical Center ChicagoChicago, IL
- Loyola Gottlieb Memorial HospitalMelrose Park, IL
- Loyola University Medical CenterMaywood, IL
- Rush Oak Park HospitalOak Park, IL
- West Suburban Medical CenterOak Park, IL
Industry payments (Open Payments)
- 2025$1,574 · 65 payments from 19 companies
- 2024$2,169 · 81 payments from 21 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Seagen Inc. | $198.99 | 2 |
| Daiichi Sankyo Inc. | $159.39 | 10 |
| Abbvie Inc. | $151.46 | 8 |
| Novartis Pharmaceuticals Corporation | $144.53 | 6 |
| Janssen Biotech, Inc. | $137.04 | 2 |
What the 2025 payments were for
- Food and Beverage$1,362 · 62 payments
- Education$211.41 · 3 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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