Medicare Enrolled
Dr. Bartosz Chmielowski, MD, PHD
Hematology & Oncology · Los Angeles, CA
Practice pattern: Mixed Practice
— Diverse clinical practice across multiple procedure types
Very High
DATA COVERAGE
Data in 4 of 4 federal sources
Measures public federal data availability — not provider quality
Informational, not a quality rating.
This page presents federal public records about Dr. Chmielowski from CMS (NPPES, Open Payments, Medicare Provider Utilization, PECOS). It is not medical advice, an endorsement, or a judgment of clinical quality. Always consult the provider directly and a licensed clinician for medical decisions. Read methodology →
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What this data tells you about Dr. Chmielowski
Dr. Bartosz Chmielowski is a hematology & oncology specialist in Los Angeles, CA, with 18 years of NPI registration. Based on federal Medicare data, Dr. Chmielowski performed 65,931 Medicare services in 2023. These records do not provide a deduplicated patient total.
Between the years covered by Open Payments, Dr. Chmielowski received a total of $67,733 from 18 pharmaceutical and/or device companies across 78 payment records. A record can group multiple payments. These transfers are publicly reported through CMS Open Payments. Disclosure alone does not establish their effect on care. A reliable breakdown by payment category is not available in this snapshot. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Chmielowski is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
✓ 18 years of NPI registration
▲ Top 12% volume in CA
$67,733 industry payments
Medicare Practice Summary — 2023
Medicare Utilization ↗65,931
Medicare services
Top 12% in CA for hematology & oncology
Not available
Unique patients (not deduplicated)
$49
Avg. Medicare payment
Medicare patients only (65+ / disabled) · How to read this →
Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Nivolumab injection (Opdivo) | 24,080 | $24 | $120 |
| Pembrolizumab injection (Keytruda) | 21,300 | $43 | $213 |
| Nivolumab and relatlimab-rmbw injection, 3 mg/1 mg An injection containing nivolumab and relatlimab-rmbw at a dose of 3 mg/1 mg. |
10,586 | $143 | $744 |
| Anti-nausea injection (fosaprepitant) An injection of fosaprepitant, a medication used to prevent nausea and vomiting. |
4,800 | $0 | $10 |
| Dexamethasone injection (steroid) An injection of dexamethasone sodium phosphate, a corticosteroid medication, administered in a dose of 1 milligram. |
544 | $0 | $5 |
| Office visit, established patient, complex (40-54 min) An office or outpatient visit for an existing patient lasting between 40 and 54 minutes. This level of service is determined by the total time spent on the date of the encounter. |
527 | $150 | $960 |
| Normal saline infusion, 250 cc Administration of 250 cubic centimeters of normal saline solution into a vein. This procedure involves the intravenous delivery of a sterile saltwater fluid. |
507 | $1 | $10 |
| Anti-nausea injection (ondansetron/Zofran) | 428 | $0 | $10 |
| Intravenous chemotherapy infusion, 1 hour or less Administration of chemotherapy medication directly into a vein. The procedure takes one hour or less to complete. |
398 | $121 | $1,065 |
| Anti-nausea injection (Aloxi/palonosetron) | 370 | $1 | $95 |
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
348 | $109 | $858 |
| Injection, potassium chloride, per 2 meq | 303 | $0 | $5 |
| Complete blood count (CBC) with differential An automated laboratory test that measures the levels of red blood cells, white blood cells, and platelets in the blood, including a breakdown of the different types of white blood cells. |
237 | $8 | $58 |
| Hospital follow-up visit, moderate complexity Follow-up hospital visit for an existing patient involving moderate medical decision making. The visit requires at least 35 minutes of time spent on the date of service. |
208 | $68 | $470 |
| Intravenous injection of additional new drug or substance Administration of an additional new medication or substance directly into a vein. |
126 | $13 | $245 |
| Additional hour of intravenous hydration This code represents each additional hour of intravenous fluid administration beyond the initial hour. It is used to bill for extended hydration therapy. |
121 | $12 | $225 |
| Additional sequential IV infusion, 1 hour or less This code represents an additional intravenous infusion administered sequentially to a primary infusion. It covers the administration time of one hour or less. |
116 | $26 | $475 |
| Comprehensive metabolic blood panel A blood test that measures a group of chemicals, including glucose, electrolytes, and kidney and liver function markers. |
107 | $10 | $67 |
| Normal saline infusion, 1000 cc Administration of 1000 cc of normal saline solution into a vein. This procedure involves the intravenous delivery of a sterile saltwater solution. |
93 | $2 | $25 |
| Magnesium sulfate injection, per 500 mg An injection of magnesium sulfate administered in 500 mg increments. |
76 | $1 | $5 |
| New patient office visit, complex (60-74 min) | 61 | $180 | $1,360 |
| Normal saline infusion, 500 ml Administration of sterile normal saline solution through an intravenous line. This procedure involves the infusion of a 500 ml unit of the solution. |
56 | $1 | $15 |
| Drug injection, under skin or into muscle A procedure involving the administration of a medication or substance via injection into the subcutaneous tissue or muscle. |
54 | $12 | $123 |
| Intravenous infusion, 1 hour or less Administration of medication or fluid directly into a vein for therapeutic, preventive, or diagnostic purposes. The procedure lasts one hour or less. |
53 | $56 | $383 |
| Intravenous hydration infusion, 31-60 minutes Administration of fluids into a vein to maintain hydration. This procedure involves an infusion lasting between 31 and 60 minutes. |
49 | $30 | $300 |
| Additional hour of intravenous infusion This code represents each additional hour of intravenous infusion beyond the initial hour for therapy, prevention, or diagnosis. |
48 | $17 | $150 |
| Diphenhydramine injection, up to 50 mg An injection of diphenhydramine hydrochloride, an antihistamine medication, administered in a dose of up to 50 milligrams. |
48 | $1 | $10 |
| Hospital follow-up visit, low complexity Follow-up hospital visit for an established patient with straightforward or low-level medical decision making. The visit requires at least 25 minutes of time spent on the day of service. |
47 | $42 | $179 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
40 | $74 | $508 |
| Additional hour of intravenous chemotherapy This code represents the administration of chemotherapy medication into a vein for each additional hour beyond the initial period. |
38 | $25 | $550 |
| Intravenous infusion of new drug or substance, 1 hour or less This procedure involves administering a new medication or substance directly into a vein through an existing access site. The infusion is completed within one hour or less. |
35 | $61 | $620 |
| Blood draw (venipuncture) Insertion of a needle into a vein to collect a blood sample. |
30 | $8 | $25 |
| Lactate dehydrogenase (LDH) level test A blood test that measures the amount of lactate dehydrogenase, an enzyme found in many body tissues. It helps assess tissue damage or disease. |
26 | $6 | $45 |
| Hospital follow-up visit, high complexity Subsequent hospital inpatient or observation care for an existing patient involving high-level medical decision making, with at least 50 minutes total time on the date of the encounter. |
22 | $102 | $680 |
| Online digital E/M service, established patient, 11-20 min An online digital evaluation and management service for an established patient. The service involves a total time of 11 to 20 minutes over a period of up to 7 days. |
20 | $26 | $143 |
| Hospital discharge day management, 30 minutes or less This service covers the final day of hospital care when the patient is being discharged. It includes coordination of care and instructions for the patient within a time frame of 30 minutes or less. |
18 | $71 | $320 |
| Initial hospital admission, high complexity Initial hospital inpatient or observation care for a new patient involving high-level medical decision making, with at least 75 minutes total time on the date of the encounter. |
11 | $149 | $1,320 |
How to read this data: This reflects Medicare patients only (typically 65+). Payment amounts are what Medicare paid the provider, not your out-of-pocket cost. These counts do not measure clinical quality or years of experience.
2.1% high complexity
95.2% medium
2.8% routine
Industry Payment Transparency
Open Payments through 2024 ↗$67,733
Total received (2018-2024)
Avg $9,676/year across 7 years
Top 10% in CA for hematology & oncology
A higher payment rank reflects disclosed industry relationships (consulting, research, speaking) common among subspecialists — not wrongdoing.
18
Companies
78
Payment records
Payments are publicly reported; disclosure does not establish legality · Not evidence of wrongdoing · How to interpret →
Payment categories are unavailable while the source breakdown is being rebuilt. Company and year totals do not identify how much belongs to each category.
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
2024
$2,473
2023
$3,049
2022
$2,504
2021
$5,047
2020
$3,616
2019
$31,100
2018
$19,944
Payments by company (2024)
SpringWorks Therapeutics, Inc.
$1,680
TriSalus Life Sciences, Inc.
$332
Abbott Laboratories
$241
Delcath Systems
$139
MACROGENICS, INC.
$65
ARRAY BIOPHARMA INC
$16
Top 3 companies account for 91.1% of 2024 payments
All-time payments by company (2018-2024) ›
Regeneron Healthcare Solutions, Inc.
$24,588
GENZYME CORPORATION
$20,817
Regeneron Pharmaceuticals, Inc.
$7,950
Novartis Pharmaceuticals Corporation
$5,704
Janssen Scientific Affairs, LLC
$3,450
Genentech USA, Inc.
$1,980
SpringWorks Therapeutics, Inc.
$1,680
TriSalus Life Sciences, Inc.
$547
Abbott Laboratories
$241
Galvanize Therapeutics, Inc
$152
Delcath Systems
$139
Deciphera Pharmaceuticals Inc.
$135
PFIZER INC.
$118
Bayer HealthCare Pharmaceuticals Inc.
$117
MACROGENICS, INC.
$65
Immunocore Limited
$23
ARRAY BIOPHARMA INC
$16
E.R. Squibb & Sons, L.L.C.
$11
Top 3 companies account for 78.8% of all-time payments
Associated products mentioned in payments ›
ALIYA SYSTEM · BRAFTOVI · Erivedge · HEPZATO KIT · KIMMTRAK · LIBTAYO · LIBTAYO CEMIPLIMAB-RWLC INJECTION · MARGENZA · MEKINIST · OPDIVO · QINLOCK · TRINAV INFUSION SYSTEM · VOTRIENT · Vitrakvi · YONDELIS
Should you be concerned? Industry payments are disclosed through CMS Open Payments. Disclosure alone does not establish their purpose, legality, or effect on care. What matters is whether a recommended drug or device appears in your doctor's payment records. If so, consider asking your doctor about it. How to interpret this data →
Geographic Context
Hematology & oncology specialists in nearby ZIP areas
354
County median income
$87,760
Nearest hospital to ZIP centroid (approximate)
RONALD REAGAN UCLA MEDICAL CENTER
0.0 mi
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | NPPES snapshot; verify current record |
| Medicare Enrollment | ✓ PECOS | PECOS snapshot |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not included | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Chmielowski is a mixed practice specialist, with above-average Medicare volume (top 12% in CA), with 18 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Chmielowski experienced with nivolumab injection (opdivo)?
Based on Medicare claims data, Dr. Chmielowski performed 24,080 nivolumab injection (opdivo) services. These records cover Medicare fee-for-service activity, including eligible younger beneficiaries; they do not measure total practice volume or clinical quality.
Does Dr. Chmielowski receive payments from pharmaceutical companies?
Yes. Dr. Chmielowski received a total of $67,733 from 18 companies across 78 payment records. A record can group multiple payments. These transfers are publicly disclosed through CMS Open Payments. Disclosure alone does not establish their legality or effect on care. Patients may wish to ask their doctor about these relationships, especially if a recommended drug or device appears in the payment records.
How do Dr. Chmielowski's costs compare to other hematology & oncology specialists in Los Angeles?
Dr. Chmielowski's average Medicare payment per service is $49. Note that these figures represent what Medicare pays, not your out-of-pocket cost, which depends on your specific insurance plan and deductible. Procedure-level data above shows both what was submitted and what Medicare paid for each service type.
What does Data Coverage mean?
Data Coverage (currently Very High for Dr. Chmielowski) measures how much public federal data is available about a provider. It is not a quality rating. A "Very High" or "High" level means the provider has data across multiple federal sources (NPPES, PECOS, Medicare Utilization, Open Payments), indicating the presence of registry, enrollment, activity or payment records, not verified experience or clinical quality. A "Low" or "Moderate" level may simply mean the provider is newer, does not see Medicare patients, or has not received any industry payments — none of which are inherently negative. Read our full methodology →
Is this data up to date?
Source publication dates and the snapshots loaded on this site can differ. Rebuilding a page does not refresh its source records. Check the Medicare reporting year and the payment interval shown above; consult the linked official sources for newer releases and current registry details. See our data freshness policy →
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About this page
This page combines public CMS records with calculated summaries and explanatory procedure labels. These transformations are not verbatim federal records. Sources: NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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