Northrop Grumman Corp., Chandler, Arizona, is being awarded a firm-fixed-price in-scope modification to a previously awarded other transaction prototype agreement. The value of this modification is $83,712,945, which increases the total value of the agreement to $239,372,600. Under this modification, the performer will continue to develop and refine their Glide Phase Intercept (GPI) concept during the technology development phase. The work will be performed in Chandler, Arizona; Linthicum, Maryland; Colorado Springs, Colorado; San Diego, California; and Huntsville, Alabama. The modification period of performance is from May 9, 2023, through March 12, 2024. This initial agreement was competitively awarded using other transaction Authority provided by 10 U.S. Code 4022 through the Enhanced Hypersonic Defense Broad Agency Announcement with Glide Phase Interceptor Special Topic, HQ0851-21-S-0001. Research, development, test, and evaluation funds will be used to fund the modification. The government will obligate in the amount of $79,237,924 at the time of award. The Missile Defense Agency, Dahlgren, Virginia, is the contracting activity (HQ08512290002).