Our proprietary λ-CapTM technology is the basis of our highly stable, fully human variable region fragment, or Fv, acceptor scaffold onto which complementary-determining regions, or CDRs, from conventional antibodies can be engrafted.
Numab stabilizes its antibody Fv fragments by exchanging a notoriously unstable part of the scaffold (FW4 of Vϰ) by a stability conferring sequence referred to as λ-CapTM (FW4 of Vλ).
A scaffold with unmatched stability
Traditionally, antibody Fv fragments have proven intractable to therapeutic use due to their inherent instability. With an elegant engineering step, Numab has overcome this hurdle by replacing a short stretch of a human variable light kappa-chain with the equivalent λ-chain stretch at the C-terminus of the light chain. This results in a fully human Fv acceptor scaffold with unmatched stability on which CDRs (complementarity determining regions) from any monoclonal antibody can be engrafted, irrespective of their origin, be it human, rodent, or rabbit. The so-called λ-CapTM constitutes a true breakthrough and endows our human acceptor scaffold with hitherto elusive stability. The resulting favorable properties have effectively turned the humanization/stabilization procedure into a routine procedure for most antibodies while maintaining their affinity and on the whole, adopting the favourable human acceptor scaffold’s biophysical properties.