Physician profile
Wallen C Chan
NPI 1043287857
$4,303.59
in general payments reported to CMS, 2019-2025
21 companies · $496 in 2025
The $496 reported for 2025 was less than what a typical Gastroenterology (Internal Medicine) provider received nationally (typical 2025 total: $636).
Payments by year
General payments by program year, as reported to CMS.
General payments by year: 2019: $709 · 2020: $235 · 2021: $771 · 2022: $725 · 2023: $857 · 2024: $512 · 2025: $496.
What the payments were for
Nature of payment as categorized by the reporting companies: meals, consulting, travel, and so on.
Food and Beverage: $1,779 · Education: $84.99.
View as a table
| Payment type | Amount (2023-2025) |
|---|---|
| Food and Beverage | $1,778.86 |
| Education | $84.99 |
Payment-type detail covers 2023-2025; earlier years are included in totals but not broken out here.
Who reported paying
General payments only, as reported to CMS. Product names cover 2023-2025.
| Company | General payments | Years | Top products |
|---|---|---|---|
| Abbvie INC. | $1,107.94 | 2019-2025 | Mavyret, Linzess, Viberzi |
| Janssen Biotech, INC. | $623.93 | 2019-2025 | Stelara, Tremfya |
| Salix Pharmaceuticals, A Division of Bausch Health US, LLC | $555.13 | 2019-2025 | Xifaxan, Trulance |
| Gilead Sciences, INC. | $477.73 | 2019-2025 | |
| Celgene Corporation | $338.15 | 2021-2023 | Zeposia |
| Takeda Pharmaceuticals U.S.A., INC. | $204.32 | 2019-2024 | Entyvio |
| Madrigal Pharmaceuticals | $181.05 | 2024-2025 | Rezdiffra |
| Intercept Pharmaceuticals, INC. | $176.55 | 2019-2023 | Ocaliva |
| Qol Medical, LLC | $124.94 | 2021-2024 | Sucraid, Sucraid |
| Merck Sharp & Dohme LLC | $107.87 | 2019-2024 | Dificid |
| Ironwood Pharmaceuticals, INC | $102.90 | 2019-2024 | Linzess |
| Phathom Pharmaceuticals, INC. | $66.31 | 2024-2025 | Voquezna |
| Nestle Healthcare Nutrition INC. | $39.86 | 2021 | |
| Exact Sciences Corporation | $31.92 | 2023 | Cologuard Collection Kit |
| Shionogi INC | $31.02 | 2019 |
Show all 21 companies
| Company | General payments | Years | Top products |
|---|---|---|---|
| Braintree Laboratories, INC. | $30.54 | 2019 | |
| Redhill Biopharma INC. | $29.77 | 2021-2022 | |
| Ferring Pharmaceuticals INC. | $24.12 | 2020-2022 | |
| Glaxosmithkline, LLC. | $19.23 | 2019 | |
| E.R. Squibb & Sons, L.L.C. | $15.94 | 2022 | |
| Pfizer INC. | $14.37 | 2019 |
Drugs and devices associated with these payments
CMS records which products a payment was associated with, not how the money was allocated. Association is not allocation: one payment can be associated with several products, and a product listing does not mean the payment was made because of that product. Product detail covers 2023-2025.
If you want to bring it up
Most clinicians are glad to talk about this. A respectful way in:
- "I saw Wallen Chan listed in the CMS Open Payments database. Can you tell me about your work with those companies?"
- "Is there a generic or alternative to this medication, and would it work as well for me?"
- "What made you choose this particular treatment for my situation?"
These are normal questions. A good clinician will welcome them.
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Source: CMS Open Payments, program years 2019-2025, as reported to CMS by drug and device makers (published June 30, 2026). Drug and device detail covers 2023-2025.