Silenseed, a leading RNAi-based therapeutics company, announced (July 14, 2015) that the United States Patent and Trademark Office (USPTO) has issued a new patent (U.S. patent no. 9,080,173) named “Methods and compositions for RNAi-based cancer treatment”” to be added to the company’s fast growing patent estate. Specifically, the patent describes the composition of matter of RNAi (RNA interference) agents for treating a patient having a solid tumor expressing a mutated K-ras protein. This is a divisional of U.S. patent application of the same name, Ser. No. 13/451,231, filed on Apr. 19, 2012.