Payment overview · 2025
General Payments
$1,064.97
41 reported records · 14 companies
Healthcare provider profile · identity verified
May Shu Chen, MD
Allopathic & Osteopathic Physicians|Internal Medicine|Nephrology · MISSION VIEJO, CA · NPI 1881772887
Verified facts
What the public records show
CMS Open Payments records show May Shu Chen, MD received $1,064.97 in general payments during 2025 across 41 reported records.
Ardelyx, Inc. accounted for 15.6% of that reported general-payment amount.
The Open Payments records used for this analysis explicitly named 12 associated products.
A separate comparison found the same explicitly named product in public Medicare Part D data: Velphoro.
Fresenius USA Marketing, 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 VELPHORO as an associated drug or biological on 8763 records involving 2642 distinct recipient NPIs. Public Medicare Part D data also shows 14 claims for Velphoro 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 |
|---|---|---|---|---|---|
| Ardelyx, Inc. | Unresolved — no canonical attribution shown | $165.65 | 15.6% | 6 | 2025 |
| Vifor Pharma, Inc. | Unresolved — no canonical attribution shown | $155.81 | 14.6% | 6 | 2025 |
| Otsuka America Pharmaceutical, Inc. | Unresolved — no canonical attribution shown | $126.56 | 11.9% | 5 | 2025 |
| SANOFI-AVENTIS U.S. LLC | Unresolved — no canonical attribution shown | $121.82 | 11.4% | 1 | 2025 |
| Novartis Pharmaceuticals Corporation | Unresolved — no canonical attribution shown | $120.18 | 11.3% | 5 | 2025 |
| Bayer Healthcare Pharmaceuticals Inc. | Unresolved — no canonical attribution shown | $71.23 | 6.7% | 4 | 2025 |
| Travere Therapeutics, Inc. | Unresolved — no canonical attribution shown | $65.11 | 6.1% | 4 | 2025 |
| Alexion Pharmaceuticals, Inc. | Unresolved — no canonical attribution shown | $48.24 | 4.5% | 2 | 2025 |
| Novo Nordisk Inc | Unresolved — no canonical attribution shown | $45.19 | 4.2% | 2 | 2025 |
| Boehringer Ingelheim Pharmaceuticals, Inc. | Unresolved — no canonical attribution shown | $37.96 | 3.6% | 2 | 2025 |
| KYOWA KIRIN, INC. | Unresolved — no canonical attribution shown | $29.98 | 2.8% | 1 | 2025 |
| Lilly USA, LLC | Unresolved — no canonical attribution shown | $27.61 | 2.6% | 1 | 2025 |
| Fresenius USA Marketing, Inc. | Unresolved — no canonical attribution shown | $25.65 | 2.4% | 1 | 2025 |
| AKEBIA THERAPEUTICS INC | Unresolved — no canonical attribution shown | $23.98 | 2.2% | 1 | 2025 |
What were the payments for?
Payment categories
| Category | Amount | Records |
|---|---|---|
| Food and Beverage | $1,064.97 | 41 |
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 |
|---|---|---|---|---|---|
| IBSRELA Normalized: ibsrela |
Drug | Ardelyx, Inc. | $165.65 | 6 | 2025 |
Source payment records
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| Veltassa Normalized: veltassa |
Drug | Vifor Pharma, Inc. | $155.81 | 6 | 2025 |
Source payment records
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| THYMOGLOBULIN Normalized: thymoglobulin |
Biological | SANOFI-AVENTIS U.S. LLC | $121.82 | 1 | 2025 |
Source payment records
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| JYNARQUE Normalized: jynarque |
Drug | Otsuka America Pharmaceutical, Inc. | $103.64 | 4 | 2025 |
Source payment records
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| Kerendia Normalized: kerendia |
Drug | Bayer Healthcare Pharmaceuticals Inc. | $71.23 | 4 | 2025 |
Source payment records
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| JARDIANCE Normalized: jardiance |
Drug | Boehringer Ingelheim Pharmaceuticals, Inc., Lilly USA, LLC | $65.57 | 3 | 2025 |
Source payment records
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| ULTOMIRIS Normalized: ultomiris |
Biological | Alexion Pharmaceuticals, Inc. | $48.24 | 2 | 2025 |
Source payment records
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| Ozempic Normalized: ozempic |
Drug | Novo Nordisk Inc | $45.19 | 2 | 2025 |
Source payment records
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| CRYSVITA Normalized: crysvita |
Drug | KYOWA KIRIN, INC. | $29.98 | 1 | 2025 |
Source payment records
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| VELPHORO Normalized: velphoro |
Drug | Fresenius USA Marketing, Inc. | $25.65 | 1 | 2025 |
Source payment records
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| Vafseo Normalized: vafseo |
Drug | AKEBIA THERAPEUTICS INC | $23.98 | 1 | 2025 |
Source payment records
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| VOYXACT Normalized: voyxact |
Drug | Otsuka America Pharmaceutical, Inc. | $22.92 | 1 | 2025 |
Source payment records
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* 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 |
|---|---|---|---|---|---|---|
| VELPHORO velphoro |
2025 | Velphoro | 2024 | 14 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 |
|---|---|---|---|---|---|---|
| Fresenius USA Marketing, Inc. Exact reporting entity; no affiliate inference |
2025 | VELPHORO open payments reported associated product |
CMS Open Payments — General Payments 8763 supporting records · 2642 recipient NPIs · example record 1244803773 |
Velphoro · 2024 Exact normalized brand match · 1 Part D row |
14 | 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 |
|---|---|---|---|
| Amlodipine Besylate | Amlodipine Besylate | 95 | 36 |
| Losartan Potassium | Losartan Potassium | 93 | 30 |
| Hydralazine Hcl | Hydralazine Hcl | 76 | 21 |
| Furosemide | Furosemide | 68 | 26 |
| Metoprolol Succinate | Metoprolol Succinate | 58 | 18 |
| Atorvastatin Calcium | Atorvastatin Calcium | 57 | 15 |
| Sevelamer Carbonate | Sevelamer Carbonate | 57 | 14 |
| Prosol | Parenteral Amino Acid 20% No.1 | 53 | suppressed |
| Carvedilol | Carvedilol | 47 | 11 |
| Calcitriol | Calcitriol | 41 | 15 |
| Pantoprazole Sodium | Pantoprazole Sodium | 38 | 11 |
| Allopurinol | Allopurinol | 35 | suppressed |
| Nifedipine Er | Nifedipine | 35 | suppressed |
| Valsartan | Valsartan | 30 | suppressed |
| Clonidine Hcl | Clonidine Hcl | 29 | suppressed |
| Calcium Acetate | Calcium Acetate | 26 | suppressed |
| Potassium Chloride | Potassium Chloride | 22 | suppressed |
| Prednisone | Prednisone | 21 | suppressed |
| Cinacalcet Hcl | Cinacalcet Hcl | 20 | suppressed |
| Torsemide | Torsemide | 19 | suppressed |
| Lisinopril | Lisinopril | 18 | suppressed |
| Tradjenta | Linagliptin | 18 | suppressed |
| Metoprolol Tartrate | Metoprolol Tartrate | 17 | suppressed |
| Levothyroxine Sodium | Levothyroxine Sodium | 16 | suppressed |
| Atenolol | Atenolol | 15 | suppressed |
| Gabapentin | Gabapentin | 15 | suppressed |
| Procrit | Epoetin Alfa | 15 | suppressed |
| Amlodipine-Olmesartan | Amlodipine Bes/Olmesartan Med | 14 | suppressed |
| Velphoro | Sucroferric Oxyhydroxide | 14 | suppressed |
| Bumetanide | Bumetanide | 13 | suppressed |
| Doxazosin Mesylate | Doxazosin Mesylate | 13 | suppressed |
| Cephalexin | Cephalexin | 12 | 12 |
| Clinisol | Parenteral Amino Acid 15% No.5 | 12 | suppressed |
| Hydrochlorothiazide | Hydrochlorothiazide | 12 | suppressed |
| Olmesartan Medoxomil | Olmesartan Medoxomil | 12 | suppressed |
| Chlorthalidone | Chlorthalidone | 11 | suppressed |
| Mirtazapine | Mirtazapine | 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 | $1,064.97 · 41 records | Ardelyx, Inc. | CRYSVITA, IBSRELA, JARDIANCE, JYNARQUE, Kerendia, Ozempic, THYMOGLOBULIN, ULTOMIRIS, VELPHORO, VOYXACT, Vafseo, Veltassa | 1 | — |
| 2024 | — | — | — | — | Complete |
Questions to ask
Questions you could discuss with your doctor
- What role, if any, does Velphoro play in your treatment recommendations for me?
- How do you evaluate evidence when you have a financial relationship with Fresenius USA Marketing, 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