# Evidence: enteric polymer

Parent: — · class: formulation design · names merged here: enteric polymer

3 papers measured or used it, 0 only mentioned it (of 207 kept papers). Papers in year order; each section heading ends with the paper's category / subcategory. Generated by tools/build_evidence.py from registry/concepts.csv and the cards; do not edit.

## 2019 Elkhabaz — Characterization of Phase Transformations for Amorphous Solid Dispersions of a Weakly Basic Drug upon Dissolution in Biorelevant Media · Dissolution / B. Supersaturation from ASD dissolution

[2019-elkhabaz-posaconazole-asd-phase-transformations-biorelevant-media](../../../cards/2019-elkhabaz-posaconazole-asd-phase-transformations-biorelevant-media/paper.html) · Dissolution / B. Supersaturation from ASD dissolution · used · as: enteric polymer

| id | kind | content | locator |
|---|---|---|---|
| C3 | claim, prior hypothesis, authors: asserted; "limited understanding" | Enteric polymers such as HPMC-AS and Eudragit L100 form suspensions under fasted gastric conditions because they are insoluble at acidic pH, delaying release to the small intestine; their effect on intraluminal supersaturation and phase behaviour, especially of the acidic suspension before intestinal pH, is poorly understood [rests on: cited: refs 24-28] | p.2 |
| C29 | claim, prior hypothesis, authors: asserted | ASDs with weakly acidic polymers such as HPMC-AS show minimal gastric release, though some posaconazole release at low pH has been reported; for a non-ionizing drug with poorly soluble polymers, release extent depended on amorphous solubility, drug loading and drug–polymer interaction strength, with more release at higher loading [rests on: cited: refs 66-69] | p.12 |
| C36 | claim, generalisation, authors: "raises questions" | Crystal formation was much greater in the 50% DL ASD, with varying levels in all formulations; this raises questions about the function of pH-dependent polymers both in controlling release and in mitigating matrix crystallization [rests on: R16, R18, R20] | p.12 |

## 2023 Nguyen — Fed- and Fasted-State Performance of Pretomanid Amorphous Solid Dispersions Formulated with an Enteric Polymer · Bioperformance / Bioperformance

[2023-nguyen-pretomanid-hpmcas-asd-fed-fasted-performance](../../../cards/2023-nguyen-pretomanid-hpmcas-asd-fed-fasted-performance/paper.html) · Bioperformance / Bioperformance · used · as: enteric polymer

| id | kind | content | locator |
|---|---|---|---|
| M3 | material | HPMCAS-HF Shin-Etsu Chemical Co., Ltd. (Tokyo, Japan) | p.3171 |
| C1 | claim, prior hypothesis, authors: asserted | Weakly acidic polymers with pH-responsive solubility are used more and more in ASDs, but drug release and crystallization at a pH where the polymer is insoluble are not well understood [rests on: argument only] | p.3170 |
| C15 | claim, prior hypothesis, authors: asserted | HF is the most hydrophobic HPMCAS grade (high acetyl:succinoyl ratio) and needs a higher pH to dissolve than the other grades [rests on: cited: refs 35, 36] | p.3174 |
| C80 | claim, prior hypothesis, authors: asserted ("well established") | Absorption from enteric-polymer dosage forms depends on delayed gastric emptying with food and on reaching an intestinal pH high enough for the polymer to dissolve; food delays and varies absorption of enteric-coated aspirin; GI pH variation explained inter-subject variability with HPMCAS-MF enteric-coated tablets [rests on: cited: refs 58, 62-64] | p.3183 |

## 2025 Junior — Release performance and crystallization of racemic and enantiopure praziquantel amorphous solid dispersion in various media · Dissolution / B. Supersaturation from ASD dissolution

[2025-alvarenga-praziquantel-racemic-enantiopure-asd-release-crystallization-media](../../../cards/2025-alvarenga-praziquantel-racemic-enantiopure-asd-release-crystallization-media/paper.html) · Dissolution / B. Supersaturation from ASD dissolution · used · as: enteric polymer

| id | kind | content | locator |
|---|---|---|---|
| C9 | claim, mechanism, authors: results: asserted ("due to"); discussion: asserted ("explaining") | HPMCAS-based ASDs release poorly at gastric pH (at most 30% in the first hour) because HPMCAS MF has low solubility below pH ∼6.0, being insoluble at gastric pH through minimal ionization of succinoyl groups; it acts as an enteric polymer dissolving at pH ∼5.5–6 [rests on: R7, R9, R10, R11, R13, R15, R17, R19; cited: refs 43, 44] | Section 3.2.1, p. 1129; Section 4.2, p. 1134 |
| M3 | material | HPMCAS-MF AQOAT AS-MF, Shin-Etsu (Tokyo, Japan) | Section 2.1, p. 1126 |