The FDA has approved BioMarin’s pegvaliase-pqpz (Palynziq), a drug for the treatment of phenylketonuria (PKU) in adults. PKU is a rare autosomal recessive disorder, affecting approximately 1 in every 10,000 to 15,000 people in the United States, that increases the levels of phenylalanine (an amino acid obtained through all dietary proteins and some artificial sweeteners) in the blood.