Spiked?

Monoclonal antibodies were viewed as a great hope for treating particularly bad Covid-19 infections (https://www.theguardian.com/world/2021/feb/02/monoclonal-antibodies-great-hope-in-covid-treatments-fails-against-variants). Monoclonals are expensive and difficult to make but treatment is fast, with no side-effects. The antibodies raised for these preparations, target the spike proteins of Sars-CoV-2 and seem to have worked very well with the original virus. The spike was chosen (as has also been the case for many of the vaccines- see later) because it is used by the virus to gain access to host cells. It was thought that the spikes couldn't change too much, without impairing the viruse's ability to enter human host cells. Worryingly, it is becoming apparent, that none of the current monoclonal antibody preparations (from GlaxoSmithKline, Eli lily or Regeneron), are active against all the recent variants of the virus (e.g. the Kent, South African and Brazilian varieties). This means that the virus has been able to change its spike proteins sufficiently for them to become unrecognisable to the monoclonals, without losing its ability to infect cells. The monoclonals can be changed to deal with the variants, but there will always be other viral mutations in the pipeline (so, maintaining effective monoclonals could become a 'war of attrition'). Makers of monoclonals are now considering trying to raise antibodies against more conserved regions of the virus. These regions, by definition, would be less subject to viable mutation than the spike proteins. It is possible that some of the current vaccines will also have to be adapted in a similar way to deal with the virus in all its forms.