Last updated: May 31, 2026
Suppliers for Doxylamine Succinate and Pyridoxine Hydrochloride (Tablets): Who Makes the API and Dosage Forms?
Doxylamine succinate and pyridoxine hydrochloride supply is split between upstream API manufacturers (for each active) and downstream formulation/finished-dose manufacturers that sell under NDA/ANDA labels. In the US, brand and generic availability typically rely on API supply chains plus contract manufacturing for combination tablets (most commonly delayed-release products and standard tablet strengths), with commercial leverage concentrated in qualified vendors that meet cGMP and regulatory expectations.
Who supplies the active ingredients (API) doxylamine succinate and pyridoxine hydrochloride?
For this combination product, suppliers fall into two groups: (1) manufacturers of doxylamine succinate API and (2) manufacturers of pyridoxine HCl API. Finished-dose makers and labelers source one or both APIs, then execute formulation and tableting under their own quality systems or via CMOs.
API supply patterns used for this drug combination
- API sourcing commonly supports multiple tablet strengths and release profiles.
- Finished-dose suppliers typically buy API from qualified upstream vendors and then control polymorph, particle size, and impurity specs per dossier requirements.
- For US commercialization, labelers depend on suppliers that can provide full quality documentation, DMF linkage (if applicable), and consistent batch release data.
Which companies supply finished-dose tablets containing doxylamine succinate + pyridoxine hydrochloride?
Finished-dose supply is handled by labelers and contract manufacturers. The specific supplier set changes over time as ANDA holders shift to different API and CMO chains, but the market generally features:
- Brand manufacturers supplying originator product
- Generic manufacturers supplying ANDA product (including authorized generics depending on the label strategy)
- CMOs producing tablets for multiple labelers under contractual manufacturing agreements
How do API and CMO supply differ for doxylamine succinate + pyridoxine hydrochloride?
API supply is driven by:
- Chemical synthesis capability for each moiety
- Control of impurity profile and residual solvents
- Stability and shelf-life for the solid APIs
CMO/finished-dose supply is driven by:
- Tablet formulation know-how (including dissolution and release performance)
- Blending and granulation control
- Packaging compatibility and stability testing
What patents protect doxylaMINE succinate and pyridoxine hydrochloride supply, formulations, and manufacturing?
This section applies to commercial freedom-to-operate more than to “suppliers” directly: patents can shape which manufacturers can make specific tablet types (e.g., delayed-release) and which manufacturing processes are protected.
Are formulation and manufacturing patents a barrier to generic suppliers?
Generic entry depends on Orange Book status and any method-of-use or formulation claims. For combination OTC/pregnancy-use drug products, the key issues are usually:
- Formulation claims (composition, ratio, excipient system, release profile)
- Process claims (manufacturing steps, granulation, compression, coating, dissolution targets)
- Method-of-use claims tied to pregnancy-related nausea and vomiting
What matters for supplier selection in a patent landscape?
Even when API is broadly available, supplier qualification is constrained by:
- Whether the intended dosage form falls inside or outside protected formulation claims
- Whether the manufacturing method infringes process claims
- Whether regulatory filings rely on specific DMF-linked processes that are tied to particular suppliers
When does exclusivity or patent protection end for this combination, affecting supplier availability?
Supplier expansion is most sensitive to exclusivity windows tied to brand product approvals and to patent expiration affecting ANDA carve-outs. Once Orange Book protections expire for the relevant strengths and dosage forms, additional generic labelers can enter, which often increases the number of potential sourcing pathways and CMOs.
How do Paragraph IV challenges affect supply?
Paragraph IV litigation impacts timing of FDA approval and launch. If entry is delayed due to injunctions or settlements, supply chains stabilize around incumbent generic suppliers. If litigation ends in favor of challengers, supplier competition usually broadens, with more CMOs and labelers drawing from the same API pools.
What is the Orange Book status of doxylamine succinate + pyridoxine hydrochloride products?
Orange Book status determines whether supplier choices are constrained by active patents for:
- The drug product (combination tablet)
- The listed formulation
- Any listed methods of use
- Any listed manufacturing methods
Why Orange Book entries matter to procurement and contracting
- If patents remain listed for a given strength and dosage form, only specific formulations or licensing routes may be commercially viable.
- If patents are expired or invalidated, procurement can broaden to additional generic manufacturers and alternative CMOs.
What generic entry risks exist for doxylamine succinate + pyridoxine hydrochloride tablets?
Generic entry risk is driven by:
- Patent infringement risk for formulation and manufacturing claims
- Regulatory approval timing and launch readiness
- Supply chain qualification (API lot release, stability, and impurities)
Which risks are biggest for procurement teams?
- Launch delay due to ongoing litigation
- Inability to meet dissolution or release requirements for certain tablet types
- Quality mismatches during API replacement or secondary sourcing
How strong is the patent estate for doxylamine succinate + pyridoxine hydrochloride?
Patent strength varies by whether the relevant claims are narrow formulation/process claims or broader composition claims. For this class of product, the most operationally important claims tend to be those that differentiate:
- delayed-release vs immediate-release
- tablet coatings and dissolution profiles
- specific excipient systems and ratios
How does this combination compare with competing pregnancy nausea drug suppliers and dosage forms?
Doxylamine succinate + pyridoxine hydrochloride is the key prescription combination for nausea/vomiting in pregnancy in the US. Competition for supply comes from:
- Other antiemetics with different active ingredients
- Alternate formulations within the same combination class (different release profiles)
- Generic and authorized generic doxylamine-pyridoxine tablets
Key Takeaways
- Supply for doxylamine succinate + pyridoxine hydrochloride is organized across API makers for each active ingredient and finished-dose manufacturers that produce combination tablets.
- Supplier qualification is shaped more by dosage form-specific formulation and process constraints than by API availability alone.
- Patent and Orange Book status for the relevant strengths and release profiles determine which manufacturers can legally commercialize specific tablet types and how quickly supplier competition expands.
- Paragraph IV litigation and settlements can shift which labelers (and their upstream vendors) get the earliest launch slots.
FAQs
1) Who are typical API suppliers for doxylamine succinate and pyridoxine hydrochloride?
API supply is split by active: doxylamine succinate API is sourced from specialized chemical manufacturers, while pyridoxine HCl API is sourced from vitamin synthesis and refinement suppliers; finished-dose makers qualify suppliers based on cGMP, impurity specs, and documentation.
2) Do suppliers need different qualification for delayed-release vs immediate-release tablets?
Yes. Release profile targets and coating/granulation processes generally require distinct formulation know-how and stability qualification.
3) How do DMFs affect supplier selection for combination tablets?
DMF linkages can tie regulatory acceptance to specific manufacturing sites and processes, making supplier substitution harder if the filing references a particular route or impurity control scheme.
4) What drives switching between API suppliers in doxylamine-pyridoxine products?
Cost, capacity, reliability, and impurity/spec compliance. Switching requires comparability work, stability, and often regulatory reporting tied to the approved application.
5) How does FDA approval pathway change who can supply finished tablets?
ANDAs can rely on bioequivalence and may source from different API/CMOs, but only those whose product and process avoid active patent claims for the targeted strength and dosage form.
References
- FDA. Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations. U.S. Food and Drug Administration. (Accessed 2026).
- FDA. FDA Drug Applications: NDAs, ANDAs, and the Drug Approval Process. U.S. Food and Drug Administration. (Accessed 2026).
