Piper Jaffray analyst Edward Tenthoff reiterates an Overweight rating on Alnylam Pharmaceuticals (ALNY) with a $142 price target after surveying 16 physicians treating 490 hereditary transthyretin amyloidosis patients with polyneuropathy. Doctors have a "clear preference" for Alnylam's Onpattro over Onpattro and Ionis Pharmaceuticals' (IONS) Tegsedi, with efficacy, safety, and experience being cited, Tenthoff tells investors in a research note. Roughly two-thirds of existing and new gene silencer patients are prescribed Onpattro, says the analyst. Based on the survey results, the analyst is increasingly confident in his 2019 Onpattro sales estimates of $127M.