Aptevo Therapeutics Inc. (APVO) SEC Filing 10-Q Quarterly report for the period ending Monday, September 30, 2019

EXHIBIT 99.1

For Immediate Release

APTEVO THERAPEUTICS REPORTS THIRD QUARTER 2019 FINANCIAL RESULTS

Reports Record Net Revenue for IXINITY;

Achieves 55% Increase in Year-over-Year Quarterly Net Revenue

Advances APVO436 Phase 1/1b Clinical Study in AML/MDS

SEATTLE, WA – November 7, 2019

“Net revenue for IXINITY^® in the third quarter of 2019 reached a record level at $9 million, representing an increase of approximately 55% year-over-year and 22% quarter-over-quarter,” said Marvin L. White, President and Chief Executive Officer.  “Our commercial organization has done a fantastic job leveraging the launch of our new 3000 IU assay and continuing to grow awareness and market share.  Based on unit volume, the third quarter of 2019 was our best quarter ever in terms of new patient conversions.  In addition to the launch of the new larger presentation we will also be commencing a pediatric study of IXINITY with the goal of obtaining a pediatric label expansion for IXINITY in the United States. We’re excited about these latest growth initiatives and continue to be very pleased with the growth trend for IXINITY and the momentum we are building around this product.”

“Our lead ADAPTIR™ clinical candidate, APVO436, is an optimized bispecific antibody that features improvements over earlier ADAPTIR candidates, including an extended half-life, enhanced potency, desirable manufacturing properties and the potential for reduced immunogenicity.  As we reported in our recent conference call, APVO436 is currently being evaluated in a Phase 1/1b clinical study in patients with acute myeloid leukemia and high-grade myelodysplastic syndrome and continues to make solid progress,” continued Mr. White.  “This is a particularly important phase of the development program for APVO436 as the preclinical and pharmacokinetic models suggest that in the upcoming dose cohorts we may achieve dose levels of APVO436 with potential clinical effect.  We expect to report ongoing progress from the APVO436 Phase 1/1b study over the next several quarters as more clinical data emerge.”

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