SUMMARY OF THE STUDY
The aim of this study was to evaluate the maximum tolerated dose of LAS02 in female Sprague Dawley rat. The study was performed as per regulatory guideline for selection of dose level for new pharmaceutical products. Animals were acclimatized in standard animal house environmental conditions at least for 5 days before the start of experiment. On last day acclimatization, the animals were randomized on the basis of their body weight . For the phase II MTD study, total 10 female SD rats with age 8-12 weak ( mean weight 155-205 g) were selected and divided into five groups. Each group has two animals in each cage. Group I was treated with 1% CM cellulose treated at dose 10 ml/kg animal body weight and serve as control, whereas group II treated twice daily with test item LAS02 at the dose level 2000mg/kg and group III treated twice daily with test item LAS02 at the dose level 1500mg/kg. Group IV animals were treated twice daily with test item LAS02 at the dose level 1000mg/kg and last group V was treated q.i.d. with test item LAS02 at the dose level 1000mg/kg body weight. Each group of animals were monitored clinical sign of toxicity and mortality per day after post dosing for seven days . Body weight, feed and water intake were measured for seven day periods. Our findings showed that no any mortality was found at the dose levels of 1000 (b.id &q.i.d) and 1500 mg/kg (b.id) in group III-V treated animals. At the dose level of 2000 mg/kg (b.i.d) , the animals of group II was died. There were no clinical sign of toxicity appeared at the dose level 1000 (b.id &q.i.d) and 1500 mg/kg (b.id) body weight. At the high dose level 2000mg/kg body wight,group I animals showed test item related clinical sign of toxicity such as slow movement, loss of haring, diarrhea and fast heart rate. The high dose treated animals showed significant decreased body weight 14% in comparison to initial day of body weight. In other treated groups, the body weight and feed and intake were not significant changes observed after post dosing of test item for 7 days. On the basis of above finding it is concluded that the maximum tolerated dose (in repeated dose ) and no observed adverse effect level (NOAEL) of test item LAS02 is 1500 mg /kg body twice in day which is correspond to human dose 243.2 mg/kg one time and LD50 of this test item is more than 2000 mg/kg body weight.
OBJECTIVE
The objective of this study was to evaluate the maximum tolerated dose of LAS02 in Sprague dawley female rat.
SAFETY PRECAUTIONS
Personal protection equipments like gloves, masks, aprons, footwear were employed as required while handling the test item and test system.
MATERIALS AND METHODS
Description of the Test Procedure
Ten Sprague dawley rats (10 female) weighting 155-205g was used for the study. All animals to be acclimatized in Standard animal house environment for at least 5 days before initiation of experiment. After the acclimatization, animals to be randomized into five groups of 02 animals each . Group I was treated with 1% CM cellulose treated at dose 10 ml/kg animal body weight and serve as control, whereas group II treated twice daily with test item LAS02 at the dose level 2000mg/kg and group III treated twice daily with test item LAS02 at the dose level 1500mg/kg. Group IV animals were treated twice daily with test item LAS02 at the dose level 1000mg/kg and last group V was treated q.i.d. with test item LAS02 at the dose level 1000mg/kg body weight. All animals were located into groups as given below.
| Groups | No of animal/Sex | Dose Intervals | Doses (mg/kg body weight) | Test Item |
|---|---|---|---|---|
| I | 2 F | BID/day | 10 ml/Kg | CMC solution |
| II | 2 F | BID/day | 2000 mg/kg | LAS02 |
| III | 2 F | BID/day | 1500 mg/Kg | LAS02 |
| IV | 2 F | BID/day | 1000mg/kg | LAS02 |
| V | 2 F | QID/day | 1000 mg/kg | LAS02 |
| BID means: Two times in a day. QID means: Four times in a day | ||||
Each group of animals were administrated dose (Ascending to descending orders order after 24 hour observation) and observed clinical sign of toxicity and mortality and body weight and food consumption record measurement for 7 days.
Preparation of Test items
Calculated amount of test item LAS02 was used according to individual body weight of animal administered via oral route. The test item was administered to animal at 10ml /Kg body weight
Justification for selection of route of administration
Oral route is the intended route for test item as suggested by the sponsor on the basis of intended use of formulation.
OBSERVATIONS
Body weight
All group of each animals were recorded body weight per day for 7 days
Feed intake
Each cage of animals were offered 200 gm per day pelleted feed and consumption was recorded next day for 7 days. Feed intake by animals were calculated by deducting the amount of feed consumed from the feed offered. The feed consumption was recorded throughout the experiment for 7 days
Clinical signs of toxicity
Clinical signs of toxicity were observed in individual animal of treated groups per day twice daily for 7 days. All clinical signs of toxicity were recorded per day in raw data sheet for 7 days.
Mortality
All animals were observed twice daily for morbidity/mortality during the entire experimental period.
Necropsy pathology
Necropsy was performed for animals in severe distress/ morbid condition and on study termination to observe any test item related toxicity.
CONCLUSION
On the basis of above parameters, it is concluded that the test item LAS02 showed repeated maximum tolerated dose (MTD) & NOAEL 1500 mg/kg body weight and LD50 2000 mg/kg body weight as evidence on the basis of body weight, feed consumption and clinical sign of toxicity parameters in SD female rats.
RESULTS
Body weight
There was significant decreased 14% body wight of higher dose treated group II as compared with initial weight of animals during period of experiment. The body weight also significant reduced in high dose (2000mg/kg ) treated group as compared with control group I. In all other dose treated groups, the body weight was found insignificant change observed from initial day and control group during period up to 7 days. (See Chart: BW & BW%)
Feed Intake
There was no drug- related impairment of food found in all treated groups except the high dose. At the high dose level, the consumption of food was found less as compared with control group. In other all treated groups, the animal consumed their feed normally. (See Chart: FI & FI%)
Deaths
No deaths occurred at dose levels 1000, 1500 mg/kg (b.i.d ) and 1000 mg/kg (q.i.d) during the observation duration. But at the dose level 2000mg/kg b.id , one animal was died on 3rd day after post dosing. On 4th day, animals of group II was completely died.