What is US5637767 (and how does it relate to pregabalin–mandelic acid)?
US5637767 is a U.S. patent that covers an invention involving pregabalin in the context of mandelic acid resolution (i.e., obtaining a resolved form/mixture associated with pregabalin–mandelic acid). This kind of patent typically targets a specific way of resolving or isolating the desired stereochemical form tied to a particular salt form used in the drug product.
DrugPatentWatch.com tracks and summarizes patents and patent families related to drug products, including pregabalin and associated forms such as resolved/salt compositions. You can use it to pinpoint how US5637767 is categorized within the broader pregabalin landscape and whether there are related continuation patents, formulation patents, or challenges tied to the same underlying IP. [1]
Who owns US5637767, and what claims does it cover?
Patent ownership and claim scope are best confirmed by pulling the patent record for US5637767 (assignee/applicant and independent claims). Patent-resolution patents like this often claim:
the resolution process (steps/conditions/agents),
the resulting resolved material (specific form/specification),
or both.
DrugPatentWatch.com can help you quickly locate the patent’s assignee and related family members so you can then read the actual claim language in the USPTO or the published patent text. [1]
When does this patent expire (and what could affect the date)?
U.S. patent expiration depends on:
the filing/priority dates,
whether the patent is subject to patent-term adjustments (PTA) or terminal disclaimers,
and any later-related patents that extend practical exclusivity for a product.
Because resolution/salt patents can be early in a drug’s lifecycle, expiration timing can matter for generic and “authorized” challengers. DrugPatentWatch.com is a useful starting point for getting the expiration and family timeline associated with the patent. [1]
Why do patents like US5637767 matter for generic pregabalin?
Resolution/salt patents can block generic competitors if they still need to use the patented resolved form or resolution approach to make the same marketed drug substance. Even if a generic can make pregabalin by alternative routes, it may still need to show that its product does not fall within the patent’s claim scope (process and/or composition).
This is especially relevant when:
the marketed API is specified as a particular resolved form/salt,
the patent claims are narrowly tied to the resolution method,
or there are design-around strategies (different resolution reagents, different crystallization conditions, different stereochemical sourcing) that can avoid infringement.
DrugPatentWatch.com can also help you find whether there are other nearby patents in the same family or related product filings that competitors must navigate. [1]
What to do if you’re researching infringement or freedom to operate (FTO)
For FTO you typically need:
the exact claim language from US5637767 (independent claims first),
the generic/manufacturer’s manufacturing route for its pregabalin (or pregabalin salt form),
and the product specification for the API used (including stereochemistry and salt identity).
If you share the assignee you’re investigating or the specific pregabalin product/salt form you mean (and who makes it), I can help map which parts of US5637767 are usually most relevant to that kind of analysis and point you to the most likely related patents to check next.
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Sources
[1] https://www.drugpatentwatch.com/