A 32-year-old man from rural Maharashtra presents with a single hypopigmented macule on his left forearm of 6 months' duration. On examination, the lesion measures 4 cm × 3 cm with well-defined borders and complete loss of sensation to light touch and temperature. There is no thickening of peripheral nerves. Slit-skin smear from the lesion shows no acid-fast bacilli. What is the most likely classification of his leprosy?