David Koch, MD
Gastroenterology · Charleston, SCNPI 1528148061
Payments from drug & device makers
What this record shows
This record is dominated by speaking fees: $39,659 of the $47,744 with a category attached, or 83.1%. Madrigal Pharmaceuticals accounts for 97.4% of it on its own, with 5 other manufacturers making up the rest. 2025 is the largest year on record at $35,063, more than ten times the $2 reported in 2019. Among gastroenterology clinicians in SC with any reported payments, this total sits in the top 5% — high for the specialty, which is a reason to read the composition above rather than the number alone.
Across 40 payments — averaging $1193.59 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Madrigal Pharmaceuticals$46K
- Edwards Lifesciences$750
- Mallinckrodt Hospital Products Inc.$323
- Ipsen Biopharmaceuticals, Inc$101
- AbbVie$82
- Travere Therapeutics, Inc.$2
What the payments were for
- Consulting fees$7502%
- Speaking & faculty fees$39,65983%
- Travel & lodging$5,52812%
- Food & beverage$1,8064%
- Education$20%
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 |
|---|---|---|
| Madrigal Pharmaceuticals | 29 | $46,486 |
| Edwards Lifesciences | 1 | $750 |
| Mallinckrodt Hospital Products Inc. | 3 | $323 |
| Ipsen Biopharmaceuticals, Inc | 2 | $101 |
| AbbVie | 3 | $82 |
| Travere Therapeutics, Inc. | 2 | $2 |
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
$47,744 in reported general payments places this provider in the 95th percentile of 259 gastroenterology providers in South Carolina.
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 |
|---|---|---|
| XifaxanRifaximin | 180 | $551,791 |
| OcalivaObeticholic Acid | 15 | $215,167 |
| Everolimus | 30 | $52,217 |
| Tacrolimus | 187 | $33,437 |
| EliquisApixaban | 18 | $26,596 |
| VemlidyTenofovir Alafenamide | 18 | $24,523 |
| Mycophenolate Mofetil | 69 | $14,437 |
| Envarsus XrTacrolimus | 23 | $10,059 |
| Ursodiol | 64 | $9,567 |
| Mycophenolic AcidMycophenolate Sodium | 30 | $7,672 |
| Azathioprine | 69 | $7,475 |
| Cyclosporine ModifiedCyclosporine, Modified | 13 | $3,061 |
| Spironolactone | 148 | $2,690 |
| Lactulose | 32 | $1,974 |
| CholestyramineCholestyramine (With Sugar) | 22 | $1,682 |
Paid to pharmacies, not to this prescriber.
Other gastroenterology in Charleston
- Erin ForsterCharleston$788K
- Mark DeleggeCharleston$568K
- Nathan ShoresCharleston$217K
- Alejandro SuarezCharleston$210K
- Peter CottonCharleston$193K
- Derek FeussnerCharleston$35K
- Darin DufaultCharleston$33K
- John LitchfieldCharleston$23K
- James SchnellCharleston$12K
- Michael SagatelianCharleston$10K
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.