Colin Diffie, MD
Rheumatology · Saint Louis, MONPI 1942616404
Payments from drug & device makers
What this record shows
This record is dominated by speaking fees: $6,188 of the $9,102 with a category attached, or 68.0%. Amgen accounts for 87.6% of it on its own, with 8 other manufacturers making up the rest.
Across 78 payments — averaging $116.69 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Amgen$8K
- AbbVie$697
- Johnson & Johnson$128
- Pfizer$120
- Novartis$91
- UCB, Inc.$33
- plus $58 from 3 others
Across 2 payments — averaging $18,009 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.
- Amgen$36K
What the payments were for
- Consulting fees$1,50016%
- Speaking & faculty fees$6,18868%
- Food & beverage$1,41416%
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 | 16 | $7,975 |
| AbbVie | 40 | $697 |
| Johnson & Johnson | 7 | $128 |
| Pfizer | 7 | $120 |
| Novartis | 4 | $91 |
| UCB, Inc. | 1 | $33 |
| Lilly USA, LLC | 1 | $28 |
| E.r. Squibb & Sons, L.L.C. | 1 | $15 |
| Boehringer Ingelheim | 1 | $15 |
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.
- Tavneos$1,500
How this compares
$9,102 in reported general payments places this provider in the 75th percentile of 134 rheumatology providers in Missouri.
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 |
|---|---|---|
| Humira(Cf) PenAdalimumab | 79 | $830,765 |
| Xeljanz XrTofacitinib Citrate | 40 | $240,359 |
| Orencia ClickjectAbatacept | 24 | $164,991 |
| Cosentyx Sensoready PenSecukinumab | 12 | $126,189 |
| EnbrelEtanercept | 15 | $116,011 |
| ActemraTocilizumab | 25 | $108,434 |
| Actemra ActpenTocilizumab | 14 | $91,924 |
| RinvoqUpadacitinib | 13 | $89,373 |
| OtezlaApremilast | 17 | $83,526 |
| XeljanzTofacitinib Citrate | 14 | $79,764 |
| BenlystaBelimumab | 11 | $52,954 |
| Hydroxychloroquine Sulfate | 231 | $9,514 |
| Mycophenolate Mofetil | 66 | $8,634 |
| RasuvoMethotrexate/Pf | 13 | $7,012 |
| MethotrexateMethotrexate Sodium | 273 | $5,255 |
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 |
|---|---|---|
| AmgenEnbrel, Otezla | $7,975 | $199,53732 claims |
| AbbVieRinvoq | $697 | $89,37313 claims |
| PfizerXeljanz | $120 | $79,76414 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 75th percentile of 134 rheumatology providers in Missouri.
Other rheumatology in Saint Louis
- Adam KilianSaint Louis$565K
- Alfred KimSaint Louis$486K
- Sona KamatSaint Louis$268K
- Richard BrasingtonSaint Louis$100K
- Akgun InceSaint Louis$45K
- Joseph StauberSaint Louis$37K
- Alissa ChandlerSaint Louis$37K
- Chad RonholmSaint Louis$27K
- Sandra HoffmannSaint Louis$23K
- John BuddSaint Louis$17K
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.