Nitrosamine risk assessment of compound amino acid injection: first distinguish which amino acids are really risky
As compound amino acid 18AA-Ⅶ injection enters the 12th batch of national procurement, only products with relevant subtypes that have been evaluated can participate in price confirmation. Many companies are making up for consistency evaluation data, and nitrosamine research is one of the difficulties. Faced with more than a dozen amino acids in a prescription, many people’s first reaction is to “check them all.” In fact, it is not necessary. The key is to clearly judge the risks first.
What's the difficulty?
Low limit. The single-day infusion volume of compound amino acids is large, and the same acceptable intake (AI) is converted into concentration, which is often only ppb level, which is much more stringent than oral preparations.
Uncertain. N-nitrosamino acids are highly polar and have poor retention in conventional reversed-phase chromatography; high concentrations of amino acids in the sample not only cause serious matrix interference, but may also react "on-site" with trace amounts of nitrite during pretreatment, causing false positives.
Many objects. Each method requires time and cost to build. If it is spread out indiscriminately, the project cycle will be very long.
Therefore, using limited testing resources on truly risky components is the core idea of research on compound amino acid nitrosamines.
CATO’s evaluation ideas
1. Find the amine source and also the “helper”
Look not only at the nitrogen atoms of the amino acids themselves, but also at what they produce when they react with other ingredients in the formula. For example, tryptophan and histidine may cyclize into secondary amines when encountering trace amounts of aldehydes, and lysine in glucose-containing prescriptions may undergo Maillard reaction to form secondary amines. At the same time, sort out the sources of nitrite: raw materials, antioxidants, water for injection, rubber stoppers and infusion bags.
2 calculation limit, converted according to daily dose
For nitrosamines without toxicological data, the AI is determined according to the FDA Carcinogenic Potency Classification (CPCA), and then converted into a concentration limit based on the maximum daily infusion volume of the product. This step determines how sensitive subsequent methods need to be.
3 points of priority, giving executable plans
Sorting according to risk: high-risk components are developed and confirmed by LC-MS/MS methods; medium- and low-risk components are supported by structural demonstration and necessary confirmatory data; reasons for eliminating risks are written. The final evaluation report can be used directly for application.
What do you think of the components in the attached picture?
Let’s start with the conclusion: The α-amino groups of these six amino acids are all primary amines. After nitrosation, unstable diazonium salts are formed and will not accumulate into stable N-nitrosamines. What you need to look at are the side chains and degradation pathways.
Components | What to pay attention to | priority |
|---|---|---|
Tryptophan | Indole NH can be directly nitrosated; when exposed to formaldehyde, it can be cyclized into tetrahydro-β-carbolinecarboxylic acid (secondary amine) | high |
Histidine | Imidazole NH; can be cyclized to spinacine (secondary amine) when encountering formaldehyde | middle |
Lysine / Ornithine | It has only primary amines; Amadori secondary amines can be produced in prescriptions containing glucose. | Depends on prescription |
Arginine | There is a certain possibility of nitrosation of guanidine NH | medium low |
Tyrosine | The phenol ring is mainly C-nitrosated and does not generate N-nitrosamines. | Low |
Another reminder: Proline and hydroxyproline in the prescription are themselves secondary amines and deserve more priority evaluation than the above.
What can CATO do?
CATO has long been engaged in drug impurity synthesis and structure confirmation, and is familiar with the nitrosation reaction mechanism. It can provide compound amino acid injections with:
· Component-by-component structure screening and nitrosation pathway analysis
· LC-MS/MS method development and validation for highly polar, high matrix samples
· Nitrosamine risk assessment report that meets the declaration requirements
CATO has passed ISO 17034 standard material producer certification (CNAS RM0030 / ANAB AR-2832 dual certification), and the data is traceable.
Companies that have compound amino acid injections under development, under review or on the market are welcome to contact CATO for nitrosamine risk assessment.
Nitrosamine risk assessment of compound amino acid injection, contact CATO
