Crystalline Forms of Isoquinoline Derivative for Drug Stability
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Solution Overview
Problem
The existing forms of {[1-cyano-5-(4-chlorophenoxy)-4-hydroxy-isoquinoline-3-carbonyl]-amino}-acetic acid (Compound A) lack stable crystalline forms with favorable physicochemical properties, which are crucial for ensuring the quality, safety, and efficacy of drug products, particularly for treating HIF-associated disorders like anemia and hypoxia.
Innovation Solution
The disclosure provides methods for preparing and characterizing crystalline forms of Compound A, specifically Form 1 and Form 2, through processes involving heating, cooling, and acid addition, with detailed XRPD and DSC characterization, ensuring stability and bioavailability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If existing forms of Compound A are used, then the compound can be synthesized, but the crystalline forms lack stability and favorable physicochemical properties
Solution Approach 1:
The patent applies parameter changes by modifying physical conditions (temperature, solvent type, pH) during crystallization to generate different crystalline forms of Compound A. Specifically, Form 1 is obtained by cooling a methanolic solution from reflux temperature, while Form 2 is obtained by adjusting pH to 2-3 with HCl. These parameter changes produce crystalline forms with distinct stability profiles and physicochemical properties, resolving the contradiction between synthesizability and stability.
Solution Approach 2:
The patent utilizes phase transitions during the crystallization process to generate stable crystalline forms. The transformation from dissolved compound in hot solvent to crystalline solid upon cooling represents a phase transition that enables the formation of stable crystalline structures. This phase transition approach directly addresses the lack of stable crystalline forms while maintaining the compound's therapeutic efficacy.
2Manufacturing precision
If crystalline forms are developed to improve stability, then manufacturing reproducibility improves, but the process complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-determining specific crystallization conditions (methanol solvent, reflux temperature, controlled cooling rate for Form 1; pH adjustment to 2-3 with HCl for Form 2) that reliably produce the desired crystalline forms. These predetermined protocols enable consistent manufacturing reproducibility without requiring complex real-time monitoring or control systems, thus improving manufacturing precision while limiting process complexity.
3Reliability
If different crystalline forms are produced, then bioavailability can be optimized, but the number of forms to characterize increases
Solution Approach 1:
The patent extracts and characterizes only the most relevant properties of each crystalline form (XRPD diffraction patterns, DSC thermal behavior, solubility, and dissolution rate) rather than attempting to measure all possible properties. This selective characterization approach enables bioavailability optimization through form selection while managing characterization complexity by focusing on the most impactful parameters.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The crystalline forms of Compound A, particularly Form 2, exhibit enhanced stability and bioavailability, effectively treating and preventing HIF-associated disorders such as anemia and hypoxia, with improved manufacturing reproducibility and chemical stability.
Implementation Method 1
having an X-ray powder diffractogram (XRPD) comprising at least one peak selected from 7.7, 11.2, 13.8, 14.7, 15.3, 15.8, 18.3, 21.1, and 22.2 °2θ ±0.2 °2θ, as determined on a diffractogram using Cu-Ka radiation
Implementation Method 2
a differential scanning calorimetry (DSC) curve that comprises an endotherm at about 251 °C
Data Source
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AI summary
The present disclosure relates to crystalline forms of {[1-cyano-5-(4-chlorophenoxy)-4-hydroxy-isoquinoline-3-carbonyl]-amino}-acetic acid (Compound A), the process of preparing crystalline forms of Compound A, the pharmaceutical compositions containing them, and the methods of use thereof.