Embodiments of the present invention relate to compositions and methods of treating patients for type 1 diabetes mellitus (T1D) by administering a therapeutically effective dose of recombinant human KLK1, variants of KLK1, or active fragments thereof. Such patients may be increase risk patients for developing T1D or T1D patients in the Honeymoon Phase. Such treatment may be expected to prevent or delay the onset of T1D, to ameliorate the symptoms of T1D, or to ameliorate the extent to which the T1D manifests.
