Subchronic Systemic Toxicity Tests

Subchronic Systemic Toxicity Tests

Test guidelines in ISO 10993-1 group both subacute and subchronic toxicity in the same general biological effect category. The duration of subacute and subchronic exposure is different. Subacute systemic toxicity is defined as the adverse effects that occur after multiple or continuous exposure between 24 hours and 28 days. Subchronic systemic toxicity is defined as the adverse effects that occur after repeated or continuous administration of a test sample to 90. days not exceeding or exceeding animal life. The rationale for the selection of a subacute or subchronic test should be based on the duration of clinical use for the medical device, the nature of exposure, and the overall test strategy. The exposure method in these tests is usually by injections of the extracts (intravenous and / or intraperitoneal) and implantation. The choice of route of exposure is based on the clinical use of the device. The injection of extracts is often used for devices that come into contact with body fluids, ie, hemodialysis and long-term use catheters (vascular and urine). This method is also useful for evaluating devices with indirect body contact or externally communicating and not intended for implantation. For implanted devices

For extract injection methods, rodents (mice or rats) are injected daily with freshly prepared device extracts. Injection volumes are typically 10-20 mL / kg body weight. Because an extract is used, clinical dose or exposure relationships are not defined, and thus, a safety factor dose cannot be determined. Animals are observed daily for signs / symptoms. Toxicity, body weights are collected weekly and food consumption can be made weekly (option). At the end of the test period, blood samples are collected for clinical pathology analysis, animals are euthanized and an autopsy is performed for 2-4 weeks. Organs were weighed for group comparison and processed for histopathology evaluation. Although ISO 10993-11 does not dictate a specific test protocol, this current standard provides guidance on the recommended parameters to be evaluated.

Toxicity studies

In vitro and in vivo animal toxicity studies are being conducted to identify and measure the short- and long-term functional and morphological side effects of a drug. Toxicity studies may include acute toxicity studies, subacute or subchronic toxicity studies, chronic toxicity studies, carcinogenicity studies, specific toxicity studies, reproductive toxicity studies, genotoxicity studies and toxicokinetic studies.

Acute toxicity studies

Acute toxicity studies are designed to measure the short-term adverse effects of the drug when administered in single or multiple doses for no more than 24 hours.

Results of acute toxicity studies:

 Doz The appropriate dose for multi-dose studies.

 Hedef Potential target toxicity organs.

 Zaman The time course of drug-induced clinical observations.

 ⦁ Species, specific differences in toxicity.

 Akut Potential for acute toxicity in humans.

 Tahmini An estimate of acute doses safe for humans.

 Subacute or subchronic studies

 Subacute or subchronic toxicity studies evaluate the toxic potential and pathological effects of a drug over a daily period of 14-90. Data on the effects observed during this study, mortality, body weight, food / water consumption, physical examination, hematology, bone marrow, coagulation, blood chemistry, urine analysis, organ weights, gross pathology and histopathology were collected and analyzed.

Chronic toxicity test

Chronic toxicity studies are performed for 1 days to 180 days. During such a study, potential risks related to the expected dose and period of drug treatment, potential toxicity targets, reversibility of observed toxicities and observed adverse effect levels (NOAELs) were observed.

Please contact us for any questions you may have regarding the Subchronic Systemic Toxicity Tests.