Dr. Mark Knapp, MD
Hematology & Oncology (Hematology & Oncology Physician)
- Medicare participating
At a glance
- Medical school
- University of Cincinnati College of Medicine (1997)
- Years since graduation
- 29
- In the NPI registry since
- 2006
- Medicare patients seen, 2024
- 412
The NPI date is when this clinician registered for a National Provider Identifier, the billing number used on health claims. It is not a license, graduation or board-certification date. NPIs were first issued in May 2005 and became required on claims in 2007–2008, so an early date usually means the clinician was already in practice before then. What an NPI is
Education and training
- 1997Medical school: University of Cincinnati College of Medicine
- 2006Registered with an NPI (national billing number; not a license date) — NPIs began in 2005, so practice likely started earlier
Undergraduate school, residency, fellowship, licensing exams and board certification aren’t in public federal data. Board certification can be confirmed with the certifying board (ABMS member boards for MDs, AOA boards for DOs).
Specialties and state licenses
-
Hematology & Oncology Physician primary
OH license 35078040 -
Medical Oncology Physician
OH license 35078040
As reported to the NPI registry. To confirm a license is current, check the state medical board.
Where they work
Hospitals
- Mount Carmel East & West Columbus, OH
- Mount Carmel St Ann's Westerville, OH
Medical groups
- American Oncology PArtners PA (391 clinicians)
Hospitals this clinician lists with Medicare, and groups they bill Medicare through (Care Compare). Affiliation doesn’t mean they see patients at every location.
Medicare patients and services
- Medicare patients, 2024
- 412
- Services billed
- 59,176
- Patients’ average age
- 75
| Service | Times | Patients |
|---|---|---|
| Injection, epoetin alfa, (for non-esrd use), 1000 units | 9,620 | 16 |
| Low osmolar contrast material, 300-399 mg/ml iodine concentration, per ml | 3,902 | 29 |
| Injection, ferric derisomaltose, 10 mg | 2,500 | 20 |
| Complete blood cell count (red cells, white blood cell, platelets), automated test and automated differential white blood cell count | 959 | 288 |
| Injection, dexamethasone sodium phosphate, 1 mg | 620 | 14 |
| Established patient office or other outpatient visit, 20-29 minutes | 489 | 313 |
| Established patient office or other outpatient visit, 30-39 minutes | 358 | 171 |
| Injection of drug or substance under skin or into muscle | 304 | 32 |
| Insertion of needle into vein for collection of blood sample | 239 | 135 |
| Administration of chemotherapy into vein, 1 hour or less | 213 | 24 |
Medicare fee-for-service only. CMS leaves out services billed for fewer than 11 patients. These figures describe a practice’s Medicare work; they aren’t a measure of quality.
Medicare prescriptions
| Drug | Prescriptions |
|---|---|
| Revlimid (lenalidomide) | 111 |
| Hydroxyurea Other prescribers in Columbus, OH | 110 |
| Dexamethasone Other prescribers in Columbus, OH | 65 |
| Imbruvica (ibrutinib) | 36 |
| Acyclovir Other prescribers in Columbus, OH | 34 |
| Pomalyst (pomalidomide) | 34 |
| Anastrozole Other prescribers in Columbus, OH | 33 |
| Prochlorperazine Maleate Other prescribers in Columbus, OH | 33 |
| Prednisone Other prescribers in Columbus, OH | 27 |
| Brukinsa (zanubrutinib) | 25 |
Prescriptions filled under Medicare Part D, including refills. CMS leaves out drugs prescribed fewer than 11 times.
Payments from drug and device companies
In 2025, 17 companies reported 39 payments worth $8,370 in total to this clinician.
| Gilead Sciences, Inc. | $5,796 |
|---|---|
| Caris Mpi, Inc. | $1,044 |
| Avyxa Pharma, LLC | $1,000 |
| Aveo Pharmaceuticals, Inc. | $78.34 |
| Eisai Inc. | $77.68 |
| E.r. Squibb & Sons, L.l.c. | $70.28 |
| Pfizer Inc. | $67.87 |
| AbbVie Inc. | $52.77 |
| Consulting Fee | $5,370 |
|---|---|
| Food and Beverage | $1,030 |
| Compensation for services other than consulting (speaking, faculty) | $1,000 |
| Travel and Lodging | $970 |
What the payments were for
| Company | What it was for | Amount |
|---|---|---|
| Gilead Sciences, Inc. Nov 26, 2025 | Consulting Fee Trodelvy · ONC Company’s description;4253500;VEM US;10434264 | $4,470 |
| Avyxa Pharma, LLC Dec 18, 2025 | Compensation for services other than consulting (speaking, faculty) | $1,000 |
| Caris Mpi, Inc. Aug 7, 2025 | Consulting Fee MI CANCER SEEK · ONCOLOGY | $900 |
| Gilead Sciences, Inc. Nov 14, 2025 | Travel and Lodging Trodelvy · ONC · travel to Chicago, IL · in-kind Company’s description;4253566;VEM US;10434264 | $356 |
| Gilead Sciences, Inc. Nov 14, 2025 | Travel and Lodging Trodelvy · ONC · travel to Chicago, IL · in-kind Company’s description;4253530;VEM US;10434264 | $351 |
| Gilead Sciences, Inc. Nov 14, 2025 | Travel and Lodging Trodelvy · ONC · travel to Chicago, IL · in-kind Company’s description;4253457;VEM US;10434264 | $220 |
| Gilead Sciences, Inc. Nov 14, 2025 | Travel and Lodging Trodelvy · ONC · travel to Chicago, IL Company’s description;4253578;VEM US;10434264 | $43.00 |
Each payment as the company reported it, with the products it named. Meals are counted in the totals above but not listed one by one.
From CMS Open Payments. A payment is not evidence of wrongdoing; many are for consulting, teaching or meals. Clinicians can review and dispute their records with CMS.
Industry-funded research
Named as a principal investigator on 3 industry-funded studies in 2025, from 3 companies. The companies reported $6,428 in research payments for these studies, mostly to the institutions running them.
- A Multicenter, Open-label, Randomized, Phase 3 Trial to Compare the Efficacy and Safety of Lenvatinib in Combination With Everolimus or Pembrolizumab Versus Sunitinib Alone in First-Line Treatment of Subjects With Adv…
Eisai Inc. - A Frontline Therapy Trial in Participants With Advanced Classical Hodgkin Lymphoma
Takeda Pharmaceuticals U.S.A., Inc. · Completed · NCT01712490 - Extended Treatment Protocol for Subjects Continuing to Benefit From Ibrutinib.
AbbVie Inc. · Active, not recruiting · NCT03229200
From CMS Open Payments research payments, where companies name up to five principal investigators per payment. Research payments usually go to hospitals, universities and research sites, not to the investigator personally. A payment is not evidence of wrongdoing.