Mark Klein, MD
Nephrology · Flowood, MSNPI 1376628529
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 97.5% of the total across 168 separate payments, which is the pattern of a clinician who attends manufacturer presentations rather than one with a consulting arrangement. It is spread thinly across 27 manufacturers, the largest accounting for just 10.9% — the pattern of someone who eats at a lot of different presentations. Reporting peaked in 2021 at $701 and has fallen 57.1% since, to $300 in 2025.
Across 168 payments — averaging $19.70 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Amgen$360
- Vifor Pharma, Inc.$282
- Bayer$274
- W. L. Gore & Associates, Inc.$272
- Akebia Therapeutics Inc$254
- AstraZeneca$237
- plus $2K from 21 others
What the payments were for
- Food & beverage$3,22697%
- Education$843%
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 |
|---|---|---|
| Amgen(2 entities) | 20 | $360 |
| Vifor Pharma, Inc. | 15 | $282 |
| Bayer | 14 | $274 |
| W. L. Gore & Associates, Inc. | 2 | $272 |
| Akebia Therapeutics Inc | 15 | $254 |
| AstraZeneca(2 entities) | 14 | $237 |
| Aurinia Pharma U.S., Inc. | 12 | $235 |
| Otsuka America Pharmaceutical, Inc. | 13 | $206 |
| Fresenius USA Marketing, Inc. | 12 | $204 |
| GSK | 9 | $138 |
| Mallinckrodt Hospital Products Inc. | 6 | $133 |
| Novartis | 5 | $131 |
| OPKO Pharmaceuticals, LLC | 9 | $125 |
| Baxter Healthcare | 1 | $89 |
| Calliditas Therapeutics US Inc. | 3 | $72 |
| Vanda Pharmaceuticals Inc. | 3 | $55 |
| Bard Peripheral Vascular, Inc. | 3 | $44 |
| Lilly USA, LLC | 2 | $38 |
| Mallinckrodt Enterprises LLC | 1 | $30 |
| Otsuka Pharmaceutical Development & Commercialization, Inc. | 1 | $20 |
| Ardelyx, Inc. | 1 | $19 |
| BD | 1 | $18 |
| Nxstage Medical, Inc. | 1 | $18 |
| Idorsia Pharmaceuticals US Inc | 1 | $16 |
| Boehringer Ingelheim | 1 | $15 |
| Genentech USA, Inc. | 1 | $13 |
| Travere Therapeutics, Inc. | 2 | $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.
How this compares
$3,310 in reported general payments places this provider in the 70th percentile of 105 nephrology providers in Mississippi.
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 |
|---|---|---|
| AuryxiaFerric Citrate | 111 | $217,622 |
| VelphoroSucroferric Oxyhydroxide | 31 | $88,077 |
| LokelmaSodium Zirconium Cyclosilicate | 25 | $20,244 |
| Lanthanum Carbonate | 27 | $19,443 |
| Sevelamer Carbonate | 103 | $18,735 |
| RenvelaSevelamer Carbonate | 24 | $16,113 |
| FarxigaDapagliflozin Propanediol | 11 | $9,886 |
| Clonidine | 15 | $2,782 |
| Calcitriol | 57 | $1,408 |
| Nifedipine ErNifedipine | 41 | $1,077 |
| Calcium Acetate | 13 | $999 |
| Furosemide | 123 | $880 |
| Losartan Potassium | 120 | $855 |
| Levothyroxine Sodium | 28 | $790 |
| Metoprolol Succinate | 52 | $640 |
Paid to pharmacies, not to this prescriber.
Companies that both paid and supply prescribed drugs
These companies both reported payments to this provider and make drugs the provider prescribed under Medicare Part D in 2024. For most specialties this overlap is expected — a cardiologist who is paid by a cardiology drugmaker also treats heart disease. It is shown so the reader can see it, not because it implies anything on its own.
| Company | Paid to this provider | Part D cost of their drugs |
|---|---|---|
| Akebia Therapeutics IncAuryxia | $254 | $217,622111 claims |
| Fresenius USA Marketing, Inc.Velphoro | $204 | $88,07731 claims |
| AstraZenecaLokelma, Farxiga | $237 | $30,12936 claims |
Reading this fairly. The Part D column is what drug plans and patients paid pharmacies — this provider received none of it, and it reflects how many patients they treat and what those drugs cost. Against peers, this provider's reported payments sit in the 70th percentile of 105 nephrology providers in Mississippi.
Other nephrology in Flowood
- Mohit AhujaFlowood$427K
- Steven WagnerFlowood$6K
- Francis PhillippiFlowood$6K
- Daphne BilbrewFlowood$6K
- Derrick TesseneerFlowood$5K
- Ami PatelFlowood$5K
- Karthikeyan VenkatachalamFlowood$5K
- Lee FergusonFlowood$4K
- Lindsey NorrisFlowood$4K
- Naveen SandhuFlowood$3K
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.