David Whittman
Nephrology · Tucson, AZNPI 1205938917
Payments from drug & device makers
What this record shows
The money is spread across several categories — consulting fees (31.9%), food and beverage and speaking fees — rather than concentrated in one kind of arrangement. Vifor Pharma, Inc. accounts for 74.3% of it on its own, with 23 other manufacturers making up the rest. Reporting peaked in 2019 at $10,170 and has fallen 94.1% since, to $596 in 2025. Among nephrology clinicians in AZ with any reported payments, this total sits in the top 10% — high for the specialty, which is a reason to read the composition above rather than the number alone.
Across 207 payments — averaging $63.64 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Vifor Pharma, Inc.$10K
- AstraZeneca$616
- OPKO Pharmaceuticals, LLC$598
- Amgen$484
- Bayer$351
- Otsuka America Pharmaceutical, Inc.$273
- plus $1K from 18 others
Across 95 payments — averaging $1558.63 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.
- Akebia Therapeutics Inc$90K
- Gilead$58K
What the payments were for
- Consulting fees$4,20032%
- Speaking & faculty fees$3,50027%
- Travel & lodging$1,27610%
- Food & beverage$3,61127%
- Education$5864%
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 |
|---|---|---|
| Vifor Pharma, Inc. | 36 | $9,794 |
| AstraZeneca(2 entities) | 28 | $616 |
| OPKO Pharmaceuticals, LLC | 34 | $598 |
| Amgen(2 entities) | 21 | $484 |
| Bayer | 21 | $351 |
| Otsuka America Pharmaceutical, Inc. | 17 | $273 |
| Novartis | 8 | $145 |
| Inari Medical, Inc. | 1 | $136 |
| Fresenius USA Marketing, Inc. | 7 | $132 |
| GSK | 5 | $94 |
| Travere Therapeutics, Inc. | 7 | $84 |
| Calliditas Therapeutics US Inc. | 3 | $72 |
| Takeda Pharmaceuticals U.S.A., Inc. | 2 | $63 |
| Novo Nordisk | 3 | $54 |
| Cormedix Inc. | 2 | $50 |
| Lilly USA, LLC | 2 | $45 |
| Ardelyx, Inc. | 2 | $42 |
| Strongbridge US Inc. | 2 | $40 |
| Leadiant Biosciences, Inc. | 1 | $22 |
| Mallinckrodt Hospital Products Inc. | 1 | $18 |
| Daiichi Sankyo Inc. | 1 | $17 |
| Otsuka Pharmaceutical Development & Commercialization, Inc. | 1 | $17 |
| Arbor Pharmaceuticals, Inc. | 1 | $15 |
| Aurinia Pharma U.S., Inc. | 1 | $12 |
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.
- Veltassa$9,055
- FLOWTRIEVER CATHETER, S$136
- CT THROMBECTOMY SYSTEM KIT$136
- LOKELMA$125
- KRYSTEXXA$125
How this compares
$13,173 in reported general payments places this provider in the 90th percentile of 259 nephrology providers in Arizona.
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 |
|---|---|---|
| RayaldeeCalcifediol | 63 | $87,633 |
| FarxigaDapagliflozin Propanediol | 65 | $84,053 |
| VelphoroSucroferric Oxyhydroxide | 17 | $63,456 |
| JardianceEmpagliflozin | 46 | $55,871 |
| EliquisApixaban | 32 | $49,542 |
| LokelmaSodium Zirconium Cyclosilicate | 35 | $44,256 |
| KerendiaFinerenone | 13 | $16,282 |
| Sevelamer Carbonate | 35 | $9,372 |
| Cinacalcet Hcl | 25 | $5,505 |
| Clonidine | 22 | $3,606 |
| Eplerenone | 44 | $3,047 |
| Fluconazole | 51 | $2,948 |
| Paricalcitol | 11 | $2,320 |
| Terazosin Hcl | 63 | $2,124 |
| Torsemide | 52 | $1,747 |
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 |
|---|---|---|
| AstraZenecaFarxiga, Lokelma | $616 | $128,309100 claims |
| OPKO Pharmaceuticals, LLCRayaldee | $598 | $87,63363 claims |
| Fresenius USA Marketing, Inc.Velphoro | $132 | $63,45617 claims |
| BayerKerendia | $351 | $16,28213 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 90th percentile of 259 nephrology providers in Arizona.
Other nephrology in Tucson
- Aneesha ShettyTucson$34K
- Bijin ThajudeenTucson$7K
- Mindy JanTucson$7K
- Tausif ZarTucson$6K
- Vincent CampionTucson$5K
- Randy CooperPeoria$597K
- Minesh RajpalPeoria$403K
- Umar WaheedPeoria$150K
- Amer KhanPeoria$71K
- Samer Bani HaniPhoenix$54K
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.