Placebo and Active Controlled, Double Dummy Study to Prove Efficacy of Aspirin in Treatment of Acute Low Back Pain

Aspirin 1000 mg (solid dose caplet) to be given three times daily as for 2 consecutive days (48 hours), followed by Aspirin 1000 mg (solid dose caplet) to be taken as per need, but not more than three times daily for the following 3 days (72 hours). Total treatment period has not to exceed 5 days and total daily dose has not to exceed 3000 mg Aspirin.

Ibuprofen 400 mg caplet to be given three times a day as for 2 consecutive days (48 hours), followed by ibuprofen 400 mg caplet to be given as per need, but not more than three times a day for the following 3 days (72 hours). Total treatment period has not to exceed 5 days and total daily dose has not to exceed 1200 mg ibuprofen.

Placebo (two placebos: Placebo Aspirin and Placebo Ibuprofen) to be given three times a day for a maximum of 5 consecutive days in the same regimen as for Experimental Drug and Active Comparator.