Healthcare provider profile · identity verified

Chang S Joo, MD

Allopathic & Osteopathic Physicians|Internal Medicine|Nephrology · MODESTO, CA · NPI 1508868787

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 Chang S Joo, MD received $17.00 in general payments during 2025 across 1 reported records.

AstraZeneca Pharmaceuticals LP accounted for 100.0% of that reported general-payment amount.

The Open Payments records used for this analysis explicitly named 1 associated product.

AstraZeneca Pharmaceuticals LP reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported LOKELMA as an associated drug or biological on 6897 records involving 4326 distinct recipient NPIs. Public Medicare Part D data also shows 33 claims for Lokelma by this doctor in 2024.

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

Payment overview · 2025

General Payments

$17.00

1 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
AstraZeneca Pharmaceuticals LP Unresolved — no canonical attribution shown $17.00100.0%12025

What were the payments for?

Payment categories

CategoryAmountRecords
Food and Beverage$17.001

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
FARXIGA
Normalized: farxiga
Drug AstraZeneca Pharmaceuticals LP $17.00 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.

Paying companyPayment yearDrug reported by same entityOpen Payments evidencePart DClaimsBeneficiaries
AstraZeneca Pharmaceuticals LP
Exact reporting entity; no affiliate inference
2025 LOKELMA
open payments reported associated product
CMS Open Payments — General Payments
6897 supporting records · 4326 recipient NPIs · example record 1206131624
Lokelma · 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

BrandGenericClaimsBeneficiaries
CalcitriolCalcitriol331102
Amlodipine BesylateAmlodipine Besylate25285
ProsolParenteral Amino Acid 20% No.1127suppressed
Losartan PotassiumLosartan Potassium12647
FurosemideFurosemide9736
Hydralazine HclHydralazine Hcl8327
Sevelamer CarbonateSevelamer Carbonate7129
Atorvastatin CalciumAtorvastatin Calcium6120
LisinoprilLisinopril4822
Potassium ChloridePotassium Chloride4212
AllopurinolAllopurinol4012
ChlorthalidoneChlorthalidone3312
LokelmaSodium Zirconium Cyclosilicate33suppressed
VeltassaPatiromer Calcium Sorbitex33suppressed
CarvedilolCarvedilol3013
Cinacalcet HclCinacalcet Hcl27suppressed
FamotidineFamotidine27suppressed
Metoprolol TartrateMetoprolol Tartrate27suppressed
HydrochlorothiazideHydrochlorothiazide25suppressed
Clonidine HclClonidine Hcl16suppressed
Lidocaine-PrilocaineLidocaine/Prilocaine16suppressed
Calcium AcetateCalcium Acetate15suppressed
Amoxicillin-Clavulanate PotassAmoxicillin/Potassium Clav1414
VelphoroSucroferric Oxyhydroxide14suppressed
Doxazosin MesylateDoxazosin Mesylate13suppressed
Metoprolol SuccinateMetoprolol Succinate13suppressed
Benazepril HclBenazepril Hcl12suppressed
ErtapenemErtapenem Sodium12suppressed
Sodium Chloride0.9 % Sodium Chloride12suppressed
TacrolimusTacrolimus12suppressed
FebuxostatFebuxostat11suppressed
MetolazoneMetolazone11suppressed

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 $17.00 · 1 records AstraZeneca Pharmaceuticals LP FARXIGA 1
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