Onconova Therapeutics Inc. delivered two pieces of information to the Street after Monday's market close, and neither sat particularly well with investors. The Newtown, Pa.-based biotech said it firmed up plans to conduct a phase III trial with the intravenous (I.V.) formulation of rigosertib in patients with higher-risk myelodysplastic syndrome (HR-MDS) who failed treatment with hypomethylating agents (HMAs).