Drugs losing US patent exclusivity in 2044
12 drugs face loss of exclusivity in 2044 · 12 small-molecule via Orange Book
What "patent cliff" means
When a drug's primary US patent expires, generic (small molecule) or biosimilar (biologic) competitors can apply to sell copies of that drug. The originator's revenue typically erodes by 30-50% within the first year of generic entry, and 60-80% within three years. For biologics, BPCIA 12-year reference product exclusivity acts as a parallel runway alongside patent protection.
2044 is long-dated (18 years away). Revenue is shielded from biosimilar / generic competition through the medium term.
Drugs losing exclusivity in 2044
| Drug | Manufacturer | Type | Earliest expiry | Patent estate | Patent classifications |
|---|---|---|---|---|---|
| Unithroid (LEVOTHYROXINE SODIUM) | Fresenius Kabi | Small molecule | 2044-09-26 | 30 patents | Formulation |
| Romvimza (VIMSELTINIB) | Deciphera Pharms | Small molecule | 2044-12-06 | 9 patents | Composition of Matter Formulation |
| Bupivacaine Hydrochloride And Epinephrine (BUPIVACAINE) | Innocoll | Small molecule | 2044-07-02 | 8 patents | Formulation Method of Use |
| mirdametinib (MIRDAMETINIB) | — | Small molecule | 2044-03-15 | 8 patents | Method of Use |
| milsaperidone (Milsaperidone) | Vanda Pharmaceuticals | Small molecule | 2044-05-31 | 7 patents | Method of Use |
| Magnesium Sulfate (Magnesium Sulfate) | Pfizer | Small molecule | 2044-06-14 | 3 patents | Formulation Method of Use |
| Artesunate (ARTESUNATE) | Amivas | Small molecule | 2044-02-16 | 2 patents | Formulation Method of Use |
| Komzifti (ZIFTOMENIB) | Kura | Small molecule | 2044-07-16 | 2 patents | Formulation Method of Use |
| vasopressin (VASOPRESSIN) | — | Small molecule | 2044-09-27 | 2 patents | Formulation |
| Microzide (hydrochlorothiazide) | Generic (originally Merck) | Small molecule | 2044-01-23 | 1 patents | Method of Use |
| Ohtuvayre (ENSIFENTRINE) | Verona Pharma | Small molecule | 2044-06-25 | 1 patents | Formulation |
| Robaxin (METHOCARBAMOL) | Hikma | Small molecule | 2044-10-09 | 1 patents | Method of Use |
Sources
- FDA Orange Book — patents listed against approved small-molecule drugs (NDAs).
- FDA Purple Book — BPCIA 12-year reference product exclusivity for licensed biologics (BLAs).
- USPTO PatentsView + Google Patents — title, abstract, and claim text grounding.
- Drug Landscape — AI-augmented enrichment and consolidated estate analysis.
Data shown is sourced from public regulatory and patent databases as of 2026-05-18. Patent term extensions, supplementary protection certificates, pediatric exclusivity, and pending IPR challenges may shift the effective expiry date. Not legal advice.