STABILITY OF CYCLOSPORINE 1-PERCENT IN ARTIFICIAL TEARS

We wished to determine the stability of frozen, refrigerated, and room temperature topical cyclosporine 1% in artificial tears (Tears Plus(R )). Cyclosporine 1% eye drops were made in artificial tears prior to t he manufacturers recommendations of using a lipid soluble vehicle, suc h as olive oil. Patients preferred the artificial tears preparation ov er the oil based cyclosporine product. Because of the good clinical re sponse and the reluctance of patients to change to the oil vehicle pro duct, we determined the stability of cyclosporine 1% in artificial tea rs. Cyclosporine 1% was prepared in artificial tears (polyvinyl alcoho l 1.4% and povidone 0.6%) by adding 1 mi of the injectable (50mg/ml) c yclosporine into 4 mi of the artificial tears solution. Each bottle wa s frozen at -20 degrees C for one month and then the cyclosporine conc entration was determined after thawing and refrigeration or storage at room temperature. Refrigerated stability was determined after thawing for up to 28 days and room temperature stability was determined for u p to 1 week after thawing. Cyclosporine concentration was determined b y HPLC analysis. None of the samples exhibited any significant loss of cyclosporine at any time period. Frozen cyclosporine appears stable w hen frozen in a 1% solution for one month. Cyclosporine 1% in artifici al tears is stable for up to 28 days in the refrigerator or at least 7 days at room temperature. Because of the ease of preparation, the pro ven clinical effectiveness of the product and better patient acceptanc e, we continue to make this product.