Payment overview · 2025
General Payments
$1,742.66
81 reported records · 39 companies
Healthcare provider profile · identity verified
Isaac Matthew Chambers, MD
Allopathic & Osteopathic Physicians|Internal Medicine|Hematology & Oncology · HAYS, KS · NPI 1497168777
Verified facts
What the public records show
CMS Open Payments records show Isaac Matthew Chambers, MD received $1,742.66 in general payments during 2025 across 81 reported records.
Janssen Biotech, Inc. accounted for 5.8% of that reported general-payment amount.
The Open Payments records used for this analysis explicitly named 56 associated products.
A separate comparison found the same explicitly named product in public Medicare Part D data: Xtandi.
ABBVIE INC. reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported CREON as an associated drug or biological on 91561 records involving 20616 distinct recipient NPIs. Public Medicare Part D data also shows 13 claims for Creon by this doctor in 2024.
Astellas Pharma US Inc reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported Xtandi as an associated drug or biological on 11345 records involving 5418 distinct recipient NPIs. Public Medicare Part D data also shows 33 claims for Xtandi by this doctor in 2024.
PFIZER INC. reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported XTANDI as an associated drug or biological on 19368 records involving 7657 distinct recipient NPIs. Public Medicare Part D data also shows 33 claims for Xtandi by this doctor in 2024.
These records do not establish that a payment influenced prescribing or medical care.
Separate record types
Research & Ownership
Research Payments (direct recipient): not present in the loaded data
Associated Research Funding (for example, named PI): not present in the loaded data
Ownership / Investment: not present in the loaded data
These categories are never added into the General Payments headline. Associated research funding must not be described as money the doctor personally received unless the source record supports that conclusion.
Who paid this doctor?
Companies in 2025 General Payments
| Reported company | Canonical company | Amount | Share | Records | Year |
|---|---|---|---|---|---|
| Janssen Biotech, Inc. | Unresolved — no canonical attribution shown | $101.35 | 5.8% | 5 | 2025 |
| PFIZER INC. | Unresolved — no canonical attribution shown | $100.03 | 5.7% | 5 | 2025 |
| Novartis Pharmaceuticals Corporation | Unresolved — no canonical attribution shown | $95.29 | 5.5% | 5 | 2025 |
| ABBVIE INC. | Unresolved — no canonical attribution shown | $87.63 | 5.0% | 4 | 2025 |
| AstraZeneca Pharmaceuticals LP | Unresolved — no canonical attribution shown | $86.28 | 5.0% | 4 | 2025 |
| SOBI, INC | Unresolved — no canonical attribution shown | $84.05 | 4.8% | 4 | 2025 |
| GlaxoSmithKline, LLC. | Unresolved — no canonical attribution shown | $78.85 | 4.5% | 4 | 2025 |
| TerSera Therapeutics LLC | Unresolved — no canonical attribution shown | $69.80 | 4.0% | 2 | 2025 |
| Rigel Pharmaceuticals, Inc. | Unresolved — no canonical attribution shown | $64.09 | 3.7% | 3 | 2025 |
| Exelixis Inc. | Unresolved — no canonical attribution shown | $63.93 | 3.7% | 3 | 2025 |
| Merck Sharp & Dohme LLC | Unresolved — no canonical attribution shown | $58.72 | 3.4% | 3 | 2025 |
| Stemline Therapeutics Inc. | Unresolved — no canonical attribution shown | $53.72 | 3.1% | 3 | 2025 |
| Gilead Sciences, Inc. | Unresolved — no canonical attribution shown | $53.65 | 3.1% | 2 | 2025 |
| Takeda Pharmaceuticals U.S.A., Inc. | Unresolved — no canonical attribution shown | $52.44 | 3.0% | 2 | 2025 |
| SpringWorks Therapeutics, Inc. | Unresolved — no canonical attribution shown | $48.04 | 2.8% | 2 | 2025 |
| Novocure Inc. | Unresolved — no canonical attribution shown | $43.59 | 2.5% | 2 | 2025 |
| Sumitomo Pharma America, Inc. | Unresolved — no canonical attribution shown | $42.39 | 2.4% | 2 | 2025 |
| Syndax Pharmaceuticals, Inc. | Unresolved — no canonical attribution shown | $41.61 | 2.4% | 2 | 2025 |
| Genentech USA, Inc. | Unresolved — no canonical attribution shown | $41.15 | 2.4% | 2 | 2025 |
| Lilly USA, LLC | Unresolved — no canonical attribution shown | $40.85 | 2.3% | 2 | 2025 |
| E.R. Squibb & Sons, L.L.C. | Unresolved — no canonical attribution shown | $33.71 | 1.9% | 2 | 2025 |
| Kite Pharma, Inc. | Unresolved — no canonical attribution shown | $32.92 | 1.9% | 1 | 2025 |
| PharmaEssentia USA Corporation | Unresolved — no canonical attribution shown | $31.99 | 1.8% | 1 | 2025 |
| Ipsen Biopharmaceuticals, Inc | Unresolved — no canonical attribution shown | $31.71 | 1.8% | 1 | 2025 |
| JAZZ PHARMACEUTICALS INC. | Unresolved — no canonical attribution shown | $25.57 | 1.5% | 1 | 2025 |
| Genmab U.S., Inc. | Unresolved — no canonical attribution shown | $23.50 | 1.4% | 1 | 2025 |
| SERVIER PHARMACEUTICALS LLC | Unresolved — no canonical attribution shown | $23.14 | 1.3% | 1 | 2025 |
| Eisai Inc. | Unresolved — no canonical attribution shown | $23.08 | 1.3% | 1 | 2025 |
| Tactile Systems Technology Inc | Unresolved — no canonical attribution shown | $22.02 | 1.3% | 1 | 2025 |
| SUN PHARMACEUTICAL INDUSTRIES INC. | Unresolved — no canonical attribution shown | $21.97 | 1.3% | 1 | 2025 |
| Daiichi Sankyo Inc. | Unresolved — no canonical attribution shown | $21.44 | 1.2% | 1 | 2025 |
| Geron Corporation | Unresolved — no canonical attribution shown | $21.23 | 1.2% | 1 | 2025 |
| Celgene Corporation | Unresolved — no canonical attribution shown | $20.71 | 1.2% | 1 | 2025 |
| Regeneron Healthcare Solutions, Inc. | Unresolved — no canonical attribution shown | $19.49 | 1.1% | 1 | 2025 |
| PUMA BIOTECHNOLOGY, INC. | Unresolved — no canonical attribution shown | $18.63 | 1.1% | 1 | 2025 |
| Legend Biotech USA Inc. | Unresolved — no canonical attribution shown | $17.22 | 1.0% | 1 | 2025 |
| Apellis Pharmaceuticals, Inc. | Unresolved — no canonical attribution shown | $16.55 | 0.9% | 1 | 2025 |
| Caris MPI, Inc. | Unresolved — no canonical attribution shown | $15.44 | 0.9% | 1 | 2025 |
| Astellas Pharma US Inc | Unresolved — no canonical attribution shown | $14.88 | 0.8% | 1 | 2025 |
What were the payments for?
Payment categories
| Category | Amount | Records |
|---|---|---|
| Food and Beverage | $1,742.66 | 81 |
A meal, consulting fee, royalty, and travel payment describe different kinds of reported relationships and should not be interpreted as equivalent.
Analysis 1 · Payment-linked products
Products named in Open Payments records
| Reported product | Type | Reported company | Related amount* | Records | Year |
|---|---|---|---|---|---|
| OJJAARA Normalized: ojjaara |
Drug | GlaxoSmithKline, LLC. | $78.85 | 4 | 2025 |
Source payment records
|
|||||
| Zoladex Normalized: zoladex |
Drug | TerSera Therapeutics LLC | $69.80 | 2 | 2025 |
Source payment records
|
|||||
| ORGOVYX Normalized: orgovyx |
Drug | PFIZER INC., Sumitomo Pharma America, Inc. | $66.92 | 3 | 2025 |
Source payment records
|
|||||
| Gavreto Normalized: gavreto |
Drug | Rigel Pharmaceuticals, Inc. | $64.09 | 3 | 2025 |
Source payment records
|
|||||
| Rezlidhia Normalized: rezlidhia |
Drug | Rigel Pharmaceuticals, Inc. | $64.09 | 3 | 2025 |
Source payment records
|
|||||
| TAVALISSE Normalized: tavalisse |
Drug | Rigel Pharmaceuticals, Inc. | $64.09 | 3 | 2025 |
Source payment records
|
|||||
| CABOMETYX Normalized: cabometyx |
Drug | Exelixis Inc. | $63.93 | 3 | 2025 |
Source payment records
|
|||||
| Doptelet Normalized: doptelet |
Drug | SOBI, INC | $60.30 | 3 | 2025 |
Source payment records
|
|||||
| KEYTRUDA Normalized: keytruda |
Biological | Merck Sharp & Dohme LLC | $58.72 | 3 | 2025 |
Source payment records
|
|||||
| ADCETRIS Normalized: adcetris |
Biological | PFIZER INC. | $57.48 | 3 | 2025 |
Source payment records
|
|||||
| ELREXFIO Normalized: elrexfio |
Drug | PFIZER INC. | $57.48 | 3 | 2025 |
Source payment records
|
|||||
| KISQALI Normalized: kisqali |
Drug | Novartis Pharmaceuticals Corporation | $54.53 | 3 | 2025 |
Source payment records
|
|||||
| Orserdu Normalized: orserdu |
Drug | Stemline Therapeutics Inc. | $53.72 | 3 | 2025 |
Source payment records
|
|||||
| Trodelvy Normalized: trodelvy |
Drug | Gilead Sciences, Inc. | $53.65 | 2 | 2025 |
Source payment records
|
|||||
| ICLUSIG Normalized: iclusig |
Drug | Takeda Pharmaceuticals U.S.A., Inc. | $52.44 | 2 | 2025 |
Source payment records
|
|||||
| OGSIVEO Normalized: ogsiveo |
Drug | SpringWorks Therapeutics, Inc. | $48.04 | 2 | 2025 |
Source payment records
|
|||||
| ERLEADA Normalized: erleada |
Drug | Janssen Biotech, Inc. | $47.93 | 2 | 2025 |
Source payment records
|
|||||
| VENCLEXTA Normalized: venclexta |
Drug | ABBVIE INC. | $46.01 | 2 | 2025 |
Source payment records
|
|||||
| Optune Lua (NovoTTF-200T) Normalized: optune lua novottf 200t |
Device | Novocure Inc. | $43.59 | 2 | 2025 |
Source payment records
|
|||||
| XTANDI Normalized: xtandi |
Drug | PFIZER INC. | $42.55 | 2 | 2025 |
Source payment records
|
|||||
| ELAHERE Normalized: elahere |
Drug | ABBVIE INC. | $41.62 | 2 | 2025 |
Source payment records
|
|||||
| BOSULIF Normalized: bosulif |
Drug | PFIZER INC. | $41.43 | 2 | 2025 |
Source payment records
|
|||||
| ENHERTU Normalized: enhertu |
Biological, Drug | AstraZeneca Pharmaceuticals LP, Daiichi Sankyo Inc. | $40.87 | 2 | 2025 |
Source payment records
|
|||||
| VERZENIO Normalized: verzenio |
Drug | Lilly USA, LLC | $40.85 | 2 | 2025 |
Source payment records
|
|||||
| LYNPARZA Normalized: lynparza |
Biological, Drug | AstraZeneca Pharmaceuticals LP, Merck Sharp & Dohme LLC | $39.67 | 2 | 2025 |
Source payment records
|
|||||
| OPDIVO Normalized: opdivo |
Biological | E.R. Squibb & Sons, L.L.C. | $33.71 | 2 | 2025 |
Source payment records
|
|||||
| Yescarta Normalized: yescarta |
Drug | Kite Pharma, Inc. | $32.92 | 1 | 2025 |
Source payment records
|
|||||
| BESREMI Normalized: besremi |
Drug | PharmaEssentia USA Corporation | $31.99 | 1 | 2025 |
Source payment records
|
|||||
| Onivyde Normalized: onivyde |
Drug | Ipsen Biopharmaceuticals, Inc | $31.71 | 1 | 2025 |
Source payment records
|
|||||
| RYBREVANT Normalized: rybrevant |
Drug | Janssen Biotech, Inc. | $28.84 | 2 | 2025 |
Source payment records
|
|||||
| Polivy Normalized: polivy |
Biological | Genentech USA, Inc. | $25.98 | 1 | 2025 |
Source payment records
|
|||||
| ZEPZELCA Normalized: zepzelca |
Drug | JAZZ PHARMACEUTICALS INC. | $25.57 | 1 | 2025 |
Source payment records
|
|||||
| DARZALEX Normalized: darzalex |
Biological | Janssen Biotech, Inc. | $24.58 | 1 | 2025 |
Source payment records
|
|||||
| TALVEY Normalized: talvey |
Biological | Janssen Biotech, Inc. | $24.58 | 1 | 2025 |
Source payment records
|
|||||
| TALZENNA Normalized: talzenna |
Drug | PFIZER INC. | $24.53 | 1 | 2025 |
Source payment records
|
|||||
| Vonjo Normalized: vonjo |
Drug | SOBI, INC | $23.75 | 1 | 2025 |
Source payment records
|
|||||
| Tivdak Normalized: tivdak |
Drug | Genmab U.S., Inc. | $23.50 | 1 | 2025 |
Source payment records
|
|||||
| Voranigo Normalized: voranigo |
Drug | SERVIER PHARMACEUTICALS LLC | $23.14 | 1 | 2025 |
Source payment records
|
|||||
| BLENREP Normalized: blenrep |
Biological | GlaxoSmithKline, LLC. | $23.10 | 1 | 2025 |
Source payment records
|
|||||
| Lenvima Normalized: lenvima |
Drug | Eisai Inc. | $23.08 | 1 | 2025 |
Source payment records
|
|||||
| Flexitouch Plus Normalized: flexitouch plus |
Device | Tactile Systems Technology Inc | $22.02 | 1 | 2025 |
Source payment records
|
|||||
| Nimbl Normalized: nimbl |
Device | Tactile Systems Technology Inc | $22.02 | 1 | 2025 |
Source payment records
|
|||||
| Odomzo Normalized: odomzo |
Drug | SUN PHARMACEUTICAL INDUSTRIES INC. | $21.97 | 1 | 2025 |
Source payment records
|
|||||
| YONSA Normalized: yonsa |
Drug | SUN PHARMACEUTICAL INDUSTRIES INC. | $21.97 | 1 | 2025 |
Source payment records
|
|||||
| Fabhalta Normalized: fabhalta |
Drug | Novartis Pharmaceuticals Corporation | $21.40 | 1 | 2025 |
Source payment records
|
|||||
| RYTELO Normalized: rytelo |
Drug | Geron Corporation | $21.23 | 1 | 2025 |
Source payment records
|
|||||
| REBLOZYL Normalized: reblozyl |
Biological | Celgene Corporation | $20.71 | 1 | 2025 |
Source payment records
|
|||||
| LIBTAYO Normalized: libtayo |
Biological | Regeneron Healthcare Solutions, Inc. | $19.49 | 1 | 2025 |
Source payment records
|
|||||
| PLUVICTO Normalized: pluvicto |
Drug | Novartis Pharmaceuticals Corporation | $19.36 | 1 | 2025 |
Source payment records
|
|||||
| WELIREG Normalized: welireg |
Drug | Merck Sharp & Dohme LLC | $18.69 | 1 | 2025 |
Source payment records
|
|||||
| NERLYNX Normalized: nerlynx |
Drug | PUMA BIOTECHNOLOGY, INC. | $18.63 | 1 | 2025 |
Source payment records
|
|||||
| CARVYKTI Normalized: carvykti |
Biological | Legend Biotech USA Inc. | $17.22 | 1 | 2025 |
Source payment records
|
|||||
| Empaveli Normalized: empaveli |
Drug | Apellis Pharmaceuticals, Inc. | $16.55 | 1 | 2025 |
Source payment records
|
|||||
| MI CANCER SEEK Normalized: mi cancer seek |
Device | Caris MPI, Inc. | $15.44 | 1 | 2025 |
Source payment records
|
|||||
| Tecentriq Normalized: tecentriq |
Biological | Genentech USA, Inc. | $15.17 | 1 | 2025 |
Source payment records
|
|||||
| Vyloy Normalized: vyloy |
Drug | Astellas Pharma US Inc | $14.88 | 1 | 2025 |
Source payment records
|
|||||
* Product-associated amounts are non-additive because one payment record may name more than one product.
These products were named on specific Open Payments records. A named product does not show that the payment influenced treatment or prescribing.
Public prescribing for products named in payments
| Open Payments product | Payment year | Part D brand | Part D year | Claims | Match method | Source |
|---|---|---|---|---|---|---|
| XTANDI xtandi |
2025 | Xtandi | 2024 | 33 Beneficiary count suppressed |
exact normalized | Medicare Part D |
The presence of the same drug in both datasets does not show that a payment caused or influenced a prescription.
Analysis 2 · Same-company prescribing overlap
Drugs reported in other payments from the same company that also appear in Medicare Part D
This analysis is independent from products named on this doctor’s individual payment records. A row appears only when the exact Open Payments reporting entity paid this doctor, that same reporting entity reported the drug or biological on at least 10 loaded General Payment records involving at least 2 distinct recipient NPIs, and this doctor has the same non-generic brand in public Part D data. This does not mean the company owns or manufactures the drug.
| Paying company | Payment year | Drug reported by same entity | Open Payments evidence | Part D | Claims | Beneficiaries |
|---|---|---|---|---|---|---|
| ABBVIE INC. Exact reporting entity; no affiliate inference |
2025 | CREON open payments reported associated product |
CMS Open Payments — General Payments 91561 supporting records · 20616 recipient NPIs · example record 1201352608 |
Creon · 2024 Exact normalized brand match · 1 Part D row |
13 | suppressed by CMS |
| Astellas Pharma US Inc Exact reporting entity; no affiliate inference |
2025 | Xtandi open payments reported associated product |
CMS Open Payments — General Payments 11345 supporting records · 5418 recipient NPIs · example record 1238560686 |
Xtandi · 2024 Exact normalized brand match · 1 Part D row |
33 | suppressed by CMS |
| PFIZER INC. Exact reporting entity; no affiliate inference |
2025 | XTANDI open payments reported associated product |
CMS Open Payments — General Payments 19368 supporting records · 7657 recipient NPIs · example record 1228794230 |
Xtandi · 2024 Exact normalized brand match · 1 Part D row |
33 | suppressed by CMS |
These facts do not show that a payment was for the drug, that the company owns or manufactures the drug, or that a payment caused or influenced prescribing.
Public Medicare Part D data
Provider-and-drug rows loaded for 2024
| Brand | Generic | Claims | Beneficiaries |
|---|---|---|---|
| Anastrozole | Anastrozole | 66 | 14 |
| Prochlorperazine Maleate | Prochlorperazine Maleate | 45 | 34 |
| Letrozole | Letrozole | 43 | suppressed |
| Tamoxifen Citrate | Tamoxifen Citrate | 42 | 11 |
| Prednisone | Prednisone | 35 | 13 |
| Gabapentin | Gabapentin | 33 | suppressed |
| Xtandi | Enzalutamide | 33 | suppressed |
| Olanzapine | Olanzapine | 23 | suppressed |
| Ondansetron Hcl | Ondansetron Hcl | 23 | 21 |
| Hydroxyurea | Hydroxyurea | 21 | suppressed |
| Levothyroxine Sodium | Levothyroxine Sodium | 18 | suppressed |
| Brukinsa | Zanubrutinib | 16 | suppressed |
| Ondansetron Odt | Ondansetron | 14 | 11 |
| Creon | Lipase/Protease/Amylase | 13 | suppressed |
| Abiraterone Acetate | Abiraterone Acetate | 12 | suppressed |
| Potassium Chloride | Potassium Chloride | 11 | suppressed |
Timeline
Payment and prescribing data by year
Open Payments and Medicare Part D may refer to different years. They are shown separately rather than aligned as if they describe the same period.
| Year | General Payments | Main payer | Explicit products | Company overlaps | Part D coverage |
|---|---|---|---|---|---|
| 2025 | $1,742.66 · 81 records | Janssen Biotech, Inc. | ADCETRIS, BESREMI, BLENREP, BOSULIF, CABOMETYX, CARVYKTI, DARZALEX, Doptelet, ELAHERE, ELREXFIO, ENHERTU, ERLEADA, Empaveli, Fabhalta, Flexitouch Plus, Gavreto, ICLUSIG, KEYTRUDA, KISQALI, LIBTAYO, LYNPARZA, Lenvima, MI CANCER SEEK, NERLYNX, Nimbl, OGSIVEO, OJJAARA, OPDIVO, ORGOVYX, Odomzo, Onivyde, Optune Lua (NovoTTF-200T), Orserdu, PLUVICTO, Polivy, REBLOZYL, RYBREVANT, RYTELO, Rezlidhia, TALVEY, TALZENNA, TAVALISSE, Tecentriq, Tivdak, Trodelvy, VENCLEXTA, VERZENIO, Vonjo, Voranigo, Vyloy, WELIREG, XTANDI, YONSA, Yescarta, ZEPZELCA, Zoladex | 3 | — |
| 2024 | — | — | — | — | Complete |
Questions to ask
Questions you could discuss with your doctor
- What role, if any, does Xtandi play in your treatment recommendations for me?
- How do you evaluate evidence when you have a financial relationship with ABBVIE INC.?
- Are there reasonable alternatives I should understand when we discuss treatment options?
- How should I interpret the industry-payment records shown here in the context of my care?
These are general questions generated from reviewed templates. They are not personalized medical advice.
Sources and limitations
How to read this page
- Payment and Medicare prescribing data can cover different years; every comparison shows both years explicitly.
- Part D does not represent a doctor’s entire practice; it excludes many patients and is subject to CMS public-release thresholds.
- Company–drug relationships must have an auditable source, a precise relationship type, and a valid evidence period. Unresolved mappings are not published.
- Generic drug claims are not attributed to a specific manufacturer without manufacturer-level evidence.
- When a source extract is incomplete, missing rows are never treated as proof of no payments or no prescriptions.
Loaded source releases
| Dataset | Year | Publication | Source |
|---|---|---|---|
| CMS Open Payments — General Payments | 2025 | 2026-06-30 | Original source |
| Medicare Part D Prescribers by Provider and Drug | 2024 | 2026-05-06 | Original source |
| NPPES Data Dissemination V2 | current / reference data | 2026-08-10 | Original source |
Full methodology · Questions & answers · Report a possible error