Nektar Therapeutics announced that efficacy data previously generated by Eli Lilly & Company for rezpegaldesleukin (REZPEG) that were presented at the September 2022 EADV Congress were incorrectly calculated by Lilly. The erroneous data is from two Phase 1b studies for REZPEG that were conducted by Lilly. The new and corrected data highlight the important potential of REZPEG to help patients battling atopic dermatitis (AtD), a chronic skin condition that afflicts nearly 10% of Americans.

Specifically, the new and corrected data from the atopic dermatitis study demonstrate that 12 weeks of REZPEG therapy at the highest dose resulted in a mean Eczema Area and Severity Index (EASI) score improvement of 83% with a p-value of 0.002 as compared to placebo and an EASI-75 response rate of 41%. REZPEG also provided a more rapid and steep drop in EASI scores immediately after therapy initiation than the previously reported erroneous data indicated. This efficacy benefit was also maintained for 36 weeks without additional treatment after the 12-week induction period.

Nektar discovered the EASI-related and Psoriasis Area and Severity Index (PASI)-related clinical efficacy endpoints were incorrectly calculated by Lilly after all rights to REZPEG were returned to Nektar and the raw data files from the REZPEG clinical studies were transferred to Nektar. This transfer of the raw data files to Nektar was the first opportunity for Nektar to review the complete patient data files. Subsequently, an independent statistical firm was employed to analyze the raw data de-novo, and the firm provided the new and corrected data in the tables below.

The internal statistical and clinical teams in charge of the two studies at Lilly were made aware that Nektar discovered the data errors. Lilly confirmed the errors in written communications with Nektar.