  We have used publicly available kinematic data for the S2 star to constrain
the parameter space of MOdified Gravity. Integrating geodesics and using a
Markov Chain Monte Carlo algorithm we have provided with the first constraint
on the scales of the Galactic Centre for the parameter $\alpha$ of the theory,
which represents the fractional increment of the gravitational constant $G$
with respect to its Newtonian value. Namely, $\alpha \lesssim 0.662$ at 99.7%
confidence level (where $\alpha = 0$ reduces the theory to General Relativity).
