A study of the stability of Ceftriaxone preparations in two vehicles for epicutaneous allergy tests
Hôpital Lariboisière, AP-HP Paris, CHU Rouen, France
Patch tests play an important role in determining the origin of drug hypersensitivity as well as in exploring the risk of cross-reactions with related molecules.
Among the patch tests performed, Ceftriaxone is the most frequently prescribed by our allergology department. Furthermore, the literature on the stability of this type of preparation is limited. Therefore, we studied the physicochemical stability of Ceftriaxone compound preparations in the form of patch tests. This approach will allow us to produce them in advance in series and to store them in appropriate conditions, allowing their good conservation, subject to registration with the ANSM as hospital preparations.
Patch tests are made from Ceftriaxone powder dispersed or diluted in two types of vehicles (white vaseline or sterile water) with a concentration of 10%. The preparations are then packaged in 3 ml syringes, labeled and then stored for 3 months at -20 ° C ± 5 ° C. The units are carried out under the conditions of use of the preparation without modifying the volume and a preparation unit is carried out for each sampling time.
The stability study is carried out in seven stages on three different batches per type of vehicle. The samples are analysed by high performance chromatography coupled to a tandem mass spectrometer at T0 (reference value) then at D2, D7, D14, D30, D60 and D90 after thawing. In order to complete our study, we also studied the stability of syringes thawed for 48 hours at 25 ° C ± 2 ° C and at 5 ° C ± 3 ° C.
Regarding the “Water” patch tests, the solution obtained at T0 was clear and slightly pale yellow. The dissolution was complete and no particles were visible to the naked eye.
The suspension obtained for the “Vaseline” tests was white in color and the dispersion was homogeneous.
After three months of storage at -20 ° ± 5 ° C, no physicochemical instability was demonstrated in the 2 vehicles. The content observed during the study was within ± 15% around the value at T0. There was also no evidence of instability in preparations thawed and then stored for two days in the refrigerator. However, there was a change in coloration of the "Water" samples thawed and stored at 25 ° C ± 2 ° C protected from light.
These results demonstrate the stability of the patch tests of Ceftriaxone at 10% in the two types of vehicles studied for 3 months at -20 ° C ± 5 ° C, which allows us to prepare these tests in advance. After thawing, the tests can be stored for 48 hours at 5 ° C ± 3 ° C.