MONMOUTH JUNCTION, N.J.--(BUSINESS WIRE)--MicroDose Therapeutx Inc. (formerly MicroDose Technologies) today announced that Merck & Co., Inc., through an affiliate, has exercised an option to extend its license to the MicroDose Dry Powder Inhaler (DPI) technology to an additional investigational compound. This option originates from the previously announced collaboration agreement between the two companies and triggers the payment of an undisclosed exercise fee to MicroDose.