  In the early 2000's, R. Langlands proposed a strategy called Beyond Endoscopy
to attack the principle of functoriality, which is one of the central questions
of present day mathematics. A first step was achieved by A. Altug who worked
with the group $GL(2,\mathbb{Q})$ in a series of three papers. We generalize
the first part of this result to a class of totally real number fields. In
particular, we cancel the contribution of the trivial and special
representations to the trace formula using an additive Poisson summation on the
regular elliptic terms.
