Pertuzumab variants and evaluation thereof

A method for making a composition comprising:

• (1) producing a composition comprising Pertuzumab and one or more variants thereof, and (2) subjecting the composition so-produced to an analytical assay to evaluate the amount of the variant(s) therein, wherein the variant(s) comprise:
• (i) unpaired cysteine variant comprising Cys23/Cys88 unpaired cysteines in one or both variable light domains of Pertuzumab;
• (ii) afucosylated variant of Pertuzumab;
• (iii) high-molecular-weight-species (HMWS) of Pertuzumab;
• or (iv) low-molecular-weight-species (LMWS) of Pertuzumab.

An isolated variant of Pertuzumab, wherein the isolated variant comprises:

• (a) an unpaired cysteine variant of Pertuzumab, wherein the variant is a heterodimer variant comprising Cys23/Cys88 unpaired cysteines in only one variable light domain of Pertuzumab;
• (b) an unpaired cysteine variant of Pertuzumab, wherein the variant is a homodimer variant comprising Cys23/Cys88 unpaired cysteines in both variable light domains of Pertuzumab;
• (c) afucosylated variant of Pertuzumab;
• (d) high-molecular-weight-species (HMWS) of Pertuzumab;
• or (e) low-molecular-weight-species (LMWS) of Pertuzumab.