Use of Transient Transfection for cGMP Manufacturing of eOD-GT8 60mer, a Self-Assembling Nanoparticle Germline-Targeting HIV-1 Vaccine Candidate

We describe the current Good Manufacturing Practice (cGMP) production and subsequent characterization of eOD-GT8 60mer, a glycosylated self-assembling nanoparticle HIV-1 vaccine candidate germline-targeting priming immunogen. Production was carried out by transient expression in the human embryonic kidney 293 (HEK293) cell line followed by a combination of purification techniques. A large scale cGMP (200 L) production run yielded 354 mg of the purified eOD-GT8 60mer drug product material, which was formulated at 1 mg/mL in 10% sucrose in phosphate-buffered saline (PBS) at pH 7.2. The clinical trial material was comprehensively characterized for purity, antigenicity, glycan composition, amino acid sequence, aggregation, and by several safety-related tests during cGMP lot release. A comparison of purified products produced at 1 L scale and 200 L cGMP scale demonstrated consistency and robustness of the transient transfection upstream process and the downstream purification strategies. The cGMP clinical trial material is being tested in a phase 1 clinical trial (NCT03547245) and is currently stored at −80°C and on a stability testing program as per regulatory guidelines. The methods described here illustrate the utility of transient transfection for cGMP production of complex products such as glycosylated self-assembling nanoparticles.