Yongen Chang, MD
Nephrology · Orange, CANPI 1932490034
Payments from drug & device makers
Across 112 payments — averaging $2856.93 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Novartis$263K
- Otsuka Pharmaceutical Development & Commercialization, Inc.$27K
- EMD Serono, Inc.$13K
- Travere Therapeutics, Inc.$11K
- Amgen$4K
- Calliditas Therapeutics US Inc.$2K
- plus $321 from 6 others
Across 1 payment — averaging $528.87 each. Payments tied to a research study. These frequently flow through the physician to a hospital or research institution rather than to the physician personally.
- Novartis$529
What the payments were for
- Consulting fees$40,43185%
- Travel & lodging$4,5089%
- Food & beverage$2,4585%
- Education$1090%
General payments by program year
Who reported the general payments
Companies are grouped under their corporate parent — a single manufacturer often files under several CMS reporting entities. Research and ownership payments are counted separately and are not in this table.
| Company | Payments | Total |
|---|---|---|
| Novartis | 11 | $263,084 |
| Otsuka Pharmaceutical Development & Commercialization, Inc. | 44 | $27,057 |
| EMD Serono, Inc. | 14 | $12,787 |
| Travere Therapeutics, Inc. | 22 | $11,001 |
| Amgen | 4 | $3,530 |
| Calliditas Therapeutics US Inc. | 8 | $2,196 |
| AstraZeneca | 1 | $95 |
| Fresenius USA Marketing, Inc. | 2 | $69 |
| GSK | 2 | $55 |
| Boehringer Ingelheim | 2 | $50 |
| Otsuka America Pharmaceutical, Inc. | 1 | $34 |
| Lilly USA, LLC | 1 | $18 |
What the payments were tied to
Products named in the reported payments. Only payments of $100 or more are attributed here — the typical reported payment nationally is a meal worth about $16, and listing those product-by-product would be noise.
How this compares
$319,976 in reported general payments places this provider in the 90th percentile of 1,341 nephrology providers in California.
Medicare billing
What this is not: this is the amount Original Medicare Part B allowed for services this provider billed in 2024. It is not their income. It excludes Medicare Advantage — now more than half of all Medicare enrollment — along with Medicaid and all commercial insurance, and it is gross practice revenue before staff, rent, supplies and malpractice premiums. CMS also suppresses any figure covering ten or fewer patients, so low-volume providers appear smaller than they are.
Most prescribed under Part D
| Drug | Claims | Cost to plans & patients |
|---|---|---|
| Sevelamer Carbonate | 19 | $6,963 |
| Calcium Acetate | 12 | $715 |
Paid to pharmacies, not to this prescriber.
Other nephrology in Orange
- Stephanie CheungOrange$1.1M
- Yasir QaziOrange$993K
- Ramy HannaOrange$923K
- Anjay RastogiLos Angeles$6.3M
- Aamir JamalSan Dimas$5.5M
- Mohamed El-ShahawyLos Angeles$4.4M
- Kalpesh PatelCalabasas$3.6M
- Jehad HaggiagiMission Hills$3.6M
- Malvin YanSouth Gate$3.3M
- Sohan DuaNorthridge$3.2M
Where these figures come from
- Payments: CMS Open Payments, program years 2019–2025 (publication P06302026_06032026).
- Billing: Medicare Physician & Other Practitioners, data year 2024. Original Medicare Part B only.
- Identity: NPPES NPI Registry, July 2026.