Sirnaomics Ltd. is gearing up to start either an expanded phase IIb or a phase III clinical trial for its lead siRNA candidate, STP-705, for the treatment of two non-melanoma skin cancers: squamous cell carcinoma in situ and basal cell carcinoma. STP-705 comprises two siRNA oligonucleotides that inhibit transforming growth factor beta 1 and cyclooxygenase-2 gene expressions and is delivered via injection using what the company describes as a polypeptide nanoparticle-enhanced delivery mechanism.