Recent experimental data on several observables in semileptonic $B$-meson decays are found to be in tension with the corresponding Standard Model predictions. Most of these deviations are related to $b \to c$ and $b \to s$ flavour changing transitions. In this talk, I plan to discuss possible New Physics effects in $b \to d \mu^+ \mu^-$ flavour changing neutral currents.
These NP contributions are parameterised in a model independent way and the $1 \sigma$ ranges of corresponding Wilson coefficients are determined from the data on the exclusive $B^\pm \to \pi^\pm \mu^+ \mu^-$ decays measured recently by the LHCb collaboration.
Afterwards, I will briefly discuss the impact of these results on other $b \to d$ processes such as the leptonic $B^0 \to \mu^+ \mu^-$ decays and $B^0 - \bar B^0$ mixing.
As an example, I will consider a simplified $Z^\prime$ model that is found to be consistent with the current $b \to d$ data in the certain regions of the NP parameters space.
In the final part of the talk, I will briefly mention other $b \to d \ell^+ \ell^-$ modes to be measured in the future