Rex Chang, MD
Family Medicine · El Segundo, CANPI 1174143622
Payments from drug & device makers
Across 15 payments — averaging $27.79 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Gilead$120
- Pfizer$88
- UCB, Inc.$55
- Teva Pharmaceuticals USA, Inc.$29
- Xeris Pharmaceuticals, Inc.$24
- Merck$20
- plus $82 from 5 others
What the payments were for
- Food & beverage$417100%
Most of this is food and beverage — typically meals provided during product presentations at a clinic or hospital. Nationally that is the single largest category of reported payments by count.
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 |
|---|---|---|
| Gilead | 1 | $120 |
| Pfizer | 4 | $88 |
| UCB, Inc. | 2 | $55 |
| Teva Pharmaceuticals USA, Inc. | 1 | $29 |
| Xeris Pharmaceuticals, Inc. | 1 | $24 |
| Merck | 1 | $20 |
| Amgen | 1 | $19 |
| Exact Sciences | 1 | $18 |
| Lilly USA, LLC | 1 | $17 |
| Abbott | 1 | $15 |
| Livanova USA, Inc. | 1 | $13 |
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.
- Vemlidy$120
How this compares
$417 in reported general payments places this provider in the 60th percentile of 10,533 family medicine 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 |
|---|---|---|
| JardianceEmpagliflozin | 16 | $13,175 |
| OzempicSemaglutide | 14 | $13,046 |
| Atrovent HfaIpratropium Bromide | 14 | $7,018 |
| Atorvastatin Calcium | 61 | $693 |
| Omeprazole | 49 | $453 |
| Baclofen | 27 | $438 |
| Duloxetine Hcl | 28 | $431 |
| Potassium Chloride | 27 | $391 |
| Albuterol Sulfate HfaAlbuterol Sulfate | 16 | $331 |
| Lisinopril | 42 | $273 |
| Meloxicam | 35 | $204 |
| Fluticasone Propionate | 23 | $185 |
| Pantoprazole Sodium | 14 | $165 |
| Losartan Potassium | 22 | $161 |
| Amlodipine Besylate | 23 | $154 |
Paid to pharmacies, not to this prescriber.
Other family medicine in El Segundo
- Amina HaggagNorthridge$112.8M
- Steven ReynoldsLong Beach$53M
- Rizwana MohseniLake Forest$26.7M
- Daniel JohnsonSan Diego$15.7M
- Stacey LayleSan Diego$14.8M
- Apinya VutikullirdCypress$14.3M
- Hanid AudishSpring Valley$13.6M
- Augusto FocilOxnard$12.6M
- Jack VuLong Beach$10.1M
- Suzanne FussellOxnard$8.9M
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.