Stability over time of the infectivity of phage ISP, lyophilized at 9 log pfu/mL, in two different stabilizers (sucrose and trehalose) at four different concentrations (0.3 M, 0.5 M, 0.8 M and 1.0 M) and stored at 4 °C, the last samples are rehydrated from an 8 year old lyophilized sample in saline and stored at 4 °C for 126 days. Data till 27 months are reproduced from Merabishvili et al. [2]. The results are the mean values of triplicate samples for all samples, except the 8 year old samples, for which three titrations performed done on single samples. Standard deviations are indicated.