Dr. John M. Wallmark, M.D.
Hematology & Oncology (Hematology & Oncology Physician)
- Medicare participating
At a glance
- Medical school
- Hahnemann University College of Medicine (1992)
- Years since graduation
- 34
- In the NPI registry since
- 2006
- Medicare patients seen, 2024
- 868
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
- 1992Medical school: Hahnemann University 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
MD license D0053177
As reported to the NPI registry. To confirm a license is current, check the state medical board.
Where they work
Hospitals
- Sibley Memorial Hospital Washington, DC
- Suburban Hospital Bethesda, MD
- Adventist Healthcare Shady Grove Medical Center Rockville, MD
- Holy Cross Germantown Hospital Germantown, MD
Medical groups
- Maryland Oncology Hematology PA (104 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
- 868
- Services billed
- 194,041
- Patients’ average age
- 76
| Service | Times | Patients |
|---|---|---|
| Injection, ferric carboxymaltose, 1 mg | 27,000 | 23 |
| Injection, darbepoetin alfa, 1 microgram (non-esrd use) | 21,360 | 33 |
| Injection, azacitidine, 1 mg | 17,200 | 13 |
| Injection, aprepitant, 1 mg | 15,600 | 36 |
| Injection, daratumumab, 10 mg and hyaluronidase-fihj | 12,240 | 17 |
| Injection, paclitaxel, 1 mg | 9,780 | 15 |
| Injection, pembrolizumab, 1 mg | 8,200 | 20 |
| Injection, denosumab, 1 mg | 6,300 | 43 |
| Injection, immune globulin, (octagam), intravenous, non-lyophilized (e.g., liquid), 500 mg | 2,860 | 20 |
| Injection, dexamethasone sodium phosphate, 1 mg | 2,122 | 44 |
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 |
|---|---|
| Letrozole Other prescribers in Rockville, MD | 205 |
| Xarelto (rivaroxaban) Other prescribers in Rockville, MD | 56 |
| Anastrozole Other prescribers in Rockville, MD | 55 |
| Warfarin Sodium Other prescribers in Rockville, MD | 49 |
| Acyclovir Other prescribers in Rockville, MD | 38 |
| Revlimid (lenalidomide) | 27 |
| Everolimus | 27 |
| Verzenio (abemaciclib) | 24 |
| Eliquis (apixaban) Other prescribers in Rockville, MD | 23 |
| Tagrisso (osimertinib mesylate) | 22 |
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, 26 companies reported 65 payments worth $2,478 in total to this clinician.
| Novartis Pharmaceuticals Corporation | $1,241 |
|---|---|
| Pfizer Inc. | $126 |
| Array Biopharma Inc | $97.94 |
| Tempus Ai, Inc | $92.18 |
| AbbVie Inc. | $90.14 |
| Genentech USA, Inc. | $79.75 |
| Stemline Therapeutics Inc. | $66.68 |
| Syndax Pharmaceuticals, Inc. | $62.71 |
| Food and Beverage | $1,478 |
|---|---|
| Long term medical supply or device loan | $1,000 |
What the payments were for
| Company | What it was for | Amount |
|---|---|---|
| Novartis Pharmaceuticals Corporation Oct 23, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Nov 26, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Dec 30, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Sep 19, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Jan 23, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Feb 21, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Mar 26, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation May 15, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Apr 24, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Jun 12, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
All 12 payments other than meals, newest first
| Company | What it was for | Amount |
|---|---|---|
| Novartis Pharmaceuticals Corporation Dec 30, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Nov 26, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Oct 23, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Sep 19, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Aug 21, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Jul 25, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Jun 12, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation May 15, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Apr 24, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Mar 26, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Feb 21, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
| Novartis Pharmaceuticals Corporation Jan 23, 2025 | Long term medical supply or device loan KISQALI · Oncology · in-kind | $83.33 |
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 7 industry-funded studies in 2025, from 5 companies. The companies reported $255,316 in research payments for these studies, mostly to the institutions running them.
- Phase 1/2 Study of Rina-S in Patients With Locally Advanced and/or Metastatic Solid Tumors
Genmab U.S., Inc. - A phase 1 dose escalation and cohort expansion study of TSR-022, an an
GlaxoSmithKline, LLC. - Randomized doubleblind phase 3 study of tucatinib or placebo in combination with adotrastuzumab emtansine TDM1 for subjects with unresectable locallyadvanced or metastatic HER2 breast cancer HER2CLIMB02
Pfizer Inc. - Endocrine Therapy With or Without Abemaciclib (LY2835219) Following Surgery in Participants With Breast Cancer
Eli Lilly and Company · Active, not recruiting · NCT03155997 - A Clinical Trial of Pembrolizumab MK-3475 Evaluating Predictive Biomarkers in Subjects with Advanced Solid Tumors KEYNOTE 158
Merck Sharp & Dohme LLC - A Study of Abiraterone Acetate Plus Prednisone With or Without Abemaciclib (LY2835219) in Participants With Prostate Cancer
Eli Lilly and Company · Active, not recruiting · NCT03706365 - A Randomized, Double-Blind, Phase III Study of Pembrolizumab versus Placebo in Combination with Neoadjuvant Chemotherapy and Adjuvant Endocrine Therapy for the Treatment of High-Risk Early-Stage Estrogen Receptor-Posi…
Merck Sharp & Dohme LLC
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.