Healthcare provider profile · identity verified

William Stephen Chung, M.D.

Allopathic & Osteopathic Physicians|Internal Medicine|Cardiovascular Disease · SAN FRANCISCO, CA · NPI 1831204486

Profile state: payments and partd Open Payments: 2025 Medicare Part D: 2024 Last identity check: 2026-08-10 Page data build: 2026-08-12

Verified facts

What the public records show

CMS Open Payments records show William Stephen Chung, M.D. received $69.71 in general payments during 2025 across 2 reported records.

SANOFI PASTEUR INC. accounted for 100.0% of that reported general-payment amount.

The Open Payments records used for this analysis explicitly named 3 associated products.

These records do not establish that a payment influenced prescribing or medical care.

Payment overview · 2025

General Payments

$69.71

2 reported records · 1 companies

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 companyCanonical companyAmountShareRecordsYear
SANOFI PASTEUR INC. Unresolved — no canonical attribution shown $69.71100.0%22025

What were the payments for?

Payment categories

CategoryAmountRecords
Food and Beverage$69.712

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 productTypeReported companyRelated amount*RecordsYear
FLUBLOK QUADRIVALENT NORTHERN HEMISPHERE
Normalized: flublok quadrivalent northern hemisphere
Biological SANOFI PASTEUR INC. $69.71 2 2025
Source payment records
FLUZONE QUADRIVALENT NORTHERN HEMISPHERE
Normalized: fluzone quadrivalent northern hemisphere
Biological SANOFI PASTEUR INC. $69.71 2 2025
Source payment records
FLUZONE HIGH-DOSE
Normalized: fluzone high dose
Biological SANOFI PASTEUR INC. $37.62 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

No exact normalized or approved-alias overlap was found in the loaded Part D year. This does not mean the doctor never prescribed the product.

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.

No publishable same-company prescribing overlap was found in the loaded Part D year. This does not mean the doctor never prescribed a drug reported elsewhere by a paying company.

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

BrandGenericClaimsBeneficiaries
Losartan PotassiumLosartan Potassium456127
Amlodipine BesylateAmlodipine Besylate29386
Atorvastatin CalciumAtorvastatin Calcium24975
SimvastatinSimvastatin18050
Metformin HclMetformin Hcl13639
CarvedilolCarvedilol12942
Levothyroxine SodiumLevothyroxine Sodium9223
Triamcinolone AcetonideTriamcinolone Acetonide9242
OmeprazoleOmeprazole8627
JanuviaSitagliptin Phosphate7415
AtenololAtenolol7221
AllopurinolAllopurinol7119
Diclofenac SodiumDiclofenac Sodium6934
Tamsulosin HclTamsulosin Hcl6522
EliquisApixaban6417
Losartan-HydrochlorothiazideLosartan/Hydrochlorothiazide6117
Pantoprazole SodiumPantoprazole Sodium5921
Metoprolol SuccinateMetoprolol Succinate5822
DigoxinDigoxin4916
Metoprolol TartrateMetoprolol Tartrate4914
XareltoRivaroxaban4914
GabapentinGabapentin4717
Trazodone HclTrazodone Hcl4318
ClopidogrelClopidogrel Bisulfate4214
GlipizideGlipizide4111
Hydralazine HclHydralazine Hcl3813
Terazosin HclTerazosin Hcl33suppressed
FinasterideFinasteride32suppressed
AzithromycinAzithromycin3129
MeloxicamMeloxicam3122
Montelukast SodiumMontelukast Sodium30suppressed
FurosemideFurosemide2815
Glipizide-MetforminGlipizide/Metformin Hcl26suppressed
Warfarin SodiumWarfarin Sodium24suppressed
Pravastatin SodiumPravastatin Sodium23suppressed
Nifedipine ErNifedipine22suppressed
Rosuvastatin CalciumRosuvastatin Calcium21suppressed
Diltiazem 24hr Er (Cd)Diltiazem Hcl20suppressed
Mometasone FuroateMometasone Furoate20suppressed
LisinoprilLisinopril19suppressed
Meclizine HclMeclizine Hcl18suppressed
Combivent RespimatIpratropium/Albuterol Sulfate17suppressed
Glipizide ErGlipizide17suppressed
HydrochlorothiazideHydrochlorothiazide17suppressed
Hydroxyzine HclHydroxyzine Hcl17suppressed
Basaglar Kwikpen U-100Insulin Glargine,hum.Rec.Anlog15suppressed
FarxigaDapagliflozin Propanediol15suppressed
NitroglycerinNitroglycerin15suppressed
Alendronate SodiumAlendronate Sodium14suppressed
JardianceEmpagliflozin14suppressed
Fluticasone PropionateFluticasone Propionate12suppressed
GlimepirideGlimepiride12suppressed
Procto-Med HcHydrocortisone11suppressed

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.

YearGeneral PaymentsMain payerExplicit productsCompany overlapsPart D coverage
2025 $69.71 · 2 records SANOFI PASTEUR INC. FLUBLOK QUADRIVALENT NORTHERN HEMISPHERE, FLUZONE HIGH-DOSE, FLUZONE QUADRIVALENT NORTHERN HEMISPHERE
2024 Complete

Questions to ask

Questions you could discuss with your doctor

These are general questions generated from reviewed templates. They are not personalized medical advice.

Sources and limitations

How to read this page

Loaded source releases

DatasetYearPublicationSource
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

Methodology version: 2.1

Editorial template version: 2.4

Product contract version: 2.0

Schema version: 0.7.0

Page data build: 2026-08-12T23:34:59.370714+00:00

Publication policy: eligible for indexing after public-launch controls are enabled

Full methodology · Questions & answers · Report a possible error