Pentadeca Arginate (PDA) — Molecular Identity & Evidence Status Reference

01What is Pentadeca Arginate?

Pentadeca Arginate — PDA, sometimes written "BPC-157 arginate" — is described by its suppliers as the fifteen-residue BPC-157 peptide presented as an arginine salt rather than the usual acetate, on the claim that the counterion improves stability. That is a claim about formulation chemistry, and it originates from manufacturers and distributors, not from published research.

This page exists in the pilot set to answer a question honestly rather than to fill a template. Searches of PubMed for the compound name, for "pentadecapeptide arginate", and for arginate in combination with BPC-157 returned no primary literature. No PubChem record for the substance was located. The molecular weight figures that circulate are vendor-derived and are presented here as such.

The important consequence is what may not be done with the BPC-157 literature. A shared peptide backbone does not transfer an evidence base: studies conducted on BPC-157 are evidence about BPC-157. Where a supplier or secondary source presents rodent tendon-healing or gastric-protection findings as PDA findings, that is extrapolation, and this database does not repeat it. Readers seeking the underlying research should consult the BPC-157 record directly, with that limitation in view.

02Molecular information

03Amino acid sequence

Structural modifications

Vendors claim, without citation, that PDA carries the same 15-residue backbone as BPC-157 (reported by vendors as GEPPPGKPADDAGLV) paired with an arginine-derived counterion in place of the acetate counterion used for BPC-157. This is a vendor claim about a claimed salt form, not a verified structural characterisation, and no independent source confirms the identity, the counterion stoichiometry, or that commercial material matches the claim. The amino_acid_count and sequence fields above are deliberately null rather than populated with BPC-157's sequence, because importing the parent compound's structure would misrepresent an unverified claim as an established fact about this product.

04Pharmacokinetic information

Half-life context

No pharmacokinetic data of any kind exist for pentadeca arginate. No half-life has been measured or reported in peer-reviewed literature, in any regulatory document, or, so far as could be determined, in any manufacturer technical documentation. Vendor pages generally do not quote one. Half-life figures published for BPC-157 in rodents do not transfer to this product: a different counterion is precisely the variable claimed to change stability and absorption, so borrowing the parent compound's numbers would assume away the only property the product is marketed on. This field is null because the value does not exist, not because it was hard to find.

05Research focus

Primary research areas

• No established research focus
• No peer-reviewed primary literature identified
• Claims are extrapolated from BPC-157 by vendors
• Marketed in the compounded and research-peptide channel
• Regulatory scrutiny of the parent compound BPC-157

Research context

There is no body of research on pentadeca arginate to summarise. This entry documents an absence of evidence, and that absence is the primary finding. Direct searches of PubMed for the exact phrase 'pentadeca arginate' return zero results, with PubMed reporting that the quoted phrase is not present in its phrase index. Searches combining 'arginate' with 'BPC 157', and for 'pentadecapeptide arginate', likewise return zero results. No PubChem compound record was located for pentadeca arginate or for BPC-157 arginate. No clinical trial, regulatory submission, pharmacopoeial monograph, or manufacturer technical dossier for this specific substance was identified. As of the date of research, no peer-reviewed primary literature exists on pentadeca arginate as a distinct entity, and at least one commercial source states this openly. What exists instead is a set of marketing claims. Vendors describe PDA as carrying the same 15-residue backbone as BPC-157, paired with an arginine-derived counterion rather than the acetate salt in which BPC-157 is normally supplied, and assert that this improves stability and oral bioavailability. Specific figures circulate, including claims that the arginate form retains over 95% structural integrity after five hours in simulated gastric fluid against under 2% for the acetate form, and that oral bioavailability exceeds 90% against under 3%. These figures are attributed on vendor pages to unpublished work by a patent holder and to an unnamed study, with no retrievable citation, no accessible data, and no independent replication. They are commercial claims, not scientific findings, and are recorded here solely to identify what is being asserted and by whom. Separately, the parent compound BPC-157 has an extensive rodent literature and appears in FDA compounding documentation: as of an FDA page updated 22 April 2026, BPC-157 is listed under bulk drug substances nominated but withdrawn, with FDA noting that compounded drugs containing it may pose immunogenicity risk for certain routes of administration and may present complexities regarding peptide-related impurities and active ingredient characterisation [1]. Pentadeca arginate is not separately listed there. None of the BPC-157 literature is evidence about pentadeca arginate.

06Research evidence and limitations

Regulatory status

Pentadeca arginate has no approval in any jurisdiction and no regulatory record of its own that could be located. It is not an FDA-approved drug, has no marketing authorisation in the EU or UK, and appears in no regulatory database examined. It is not separately named on FDA's compounding bulk drug substances pages. The nearest applicable regulatory context concerns the parent compound: on the FDA page 'Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks', last updated 22 April 2026, BPC-157 appears under bulk drug substances nominated but withdrawn, with FDA stating that compounded drugs containing BPC-157 may pose risk for immunogenicity for certain routes of administration and may have complexities with regard to peptide-related impurities and active pharmaceutical ingredient characterisation, and that FDA lacks sufficient safety information to determine whether the substance would cause harm when administered to humans [1]. The state of that listing has changed more than once and should be re-checked at publication time. Material sold as pentadeca arginate is supplied as a research chemical or through compounding channels, outside any framework that has assessed its identity, purity, safety or effect. Marketing that positions PDA as a next-generation or improved successor to BPC-157 is making a commercial claim about a substance that no regulator has evaluated.

07Research material and sourcing notes

Reported research-use reconstitution information

Not documented in any literature or regulatory source. Reconstitution instructions circulating for PDA (typically reconstitution with bacteriostatic water and gentle swirling rather than shaking) appear only on vendor and reseller pages and are explicitly vendor-derived. They are generic lyophilised-peptide handling instructions rather than product-specific data, carry no supporting stability study, and are reproduced here only to identify their source type. No dosing guidance is given.

Reported storage and stability information

Not documented in any literature or regulatory source. Storage figures in circulation (typically -20°C for long-term lyophilised storage, 2 to 8°C short term, and a claimed 2 to 4 week window after reconstitution under refrigeration) are vendor-derived and are not supported by any published stability study specific to this material. They should be labelled as vendor claims wherever reproduced.

Identity and sourcing notes

Sourcing risk here is at the maximum, because identity cannot be established by any means available to a buyer. There is no reference standard, no published analytical method, no pharmacopoeial monograph and no agreed specification for pentadeca arginate, so there is nothing authoritative to test material against. Naming is unstable: pentadeca arginate, PDA, BPC-157 arginate, pentadecapeptide arginate and penta deca peptide arginate are used interchangeably in commerce with no standards body governing any of them, and 'PDA' collides with many unrelated abbreviations. The counterion stoichiometry, the one property the product is sold on, is not specified by any source, so two vials both labelled PDA may differ materially. A certificate of analysis for this material has unusually narrow value. At best it can report a mass consistent with a 15-residue peptide and a purity percentage against whatever the supplier chose as the target. It cannot confirm the arginate salt form or its ratio without explicit ion chromatography or equivalent counterion analysis, which is rarely included; it cannot confirm stereochemistry across fifteen residues; it cannot detect deletion or truncation sequences unless the method resolves them; and it says nothing about endotoxin, bioburden or residual solvents unless those are separately reported. A COA showing 99% purity for a substance with no defined identity is a statement about a chromatogram, not about what the material is. Seller-issued COAs without an independent laboratory, an instrument trace, and a batch number matching the vial should carry minimal weight. This is informational only and is not a recommendation to obtain or use this material.

08References and evidence

Primary sources

1. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks (BPC-157 entry under substances nominated but withdrawn)regulatoryUS Food and Drug Administration — FDA, page last updated 22 April 2026
2. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act (Category 1/2/3 framework)regulatoryUS Food and Drug Administration — FDA

Chemical and molecular databases

• PubMed search for "pentadeca arginate" — zero results (phrase not in PubMed's phrase index)
• PubMed search for "arginate" AND "BPC 157" — zero results
• PubChem CID 9941957 (BPC-157, the parent compound — NOT pentadeca arginate)
• VENDOR-DERIVED: SeekPeptides — source of the simulated-gastric-fluid stability and oral bioavailability claims, attributed to unpublished patent-holder research with no retrievable citation
• VENDOR-DERIVED: The Peptide Catalog — commercial page that itself states there are no peer-reviewed studies on PDA as a distinct molecule

09Related compounds

• BPC-157The claimed parent compound; PDA is marketed as the same 15-residue backbone in an arginate rather than acetate salt form, though this relationship is a vendor claim and is not independently verified.
• KPVA short peptide marketed in the same gut and inflammation-focused research-peptide category, and frequently sold alongside PDA on the same channels.Reference page in preparation
• TB-500 (as Thymosin β4)Routinely paired with BPC-157 and PDA in tissue-repair marketing, and shares the same pattern of rodent-only evidence with no adequate human trials.
• GHK-CuAnother repair-and-remodelling peptide in the same commercial category, and a useful contrast because it does have a defined structure and registry identifiers that PDA lacks.
• LL-37A well-characterised endogenous host-defence peptide sold in the same channel, illustrating what a properly characterised peptide entry looks like relative to PDA.Reference page in preparation

10Frequently asked questions