Helix Biopharma Corp., of Aurora, Ontario, said it opened patient screening in the second dosing cohort of its ongoing phase I study of L-DOS47 in combination with pemetrexed/carboplatin. The safety review committee reviewed safety data from the first dosing cohort and recommended that Helix begin enrollment of patients into the second cohort, to receive 0.78 mcg of L-DOS47 per kilogram of patient body weight.