According to the definitions acceptable to most scientists, there may be at least 5 intelligent species on Earth (humans count as 1). You must be careful about limiting the definition (for example, excluding the other 4) because you could end up excluding a large proportion of the human race.
We do not know if there is life on some other planet. However, given the way chemistry works (for example, the nonrandom way in which elements assemble to form molecules), life should be easy to achieve, given the right conditions.
Will this life evolve into "intelligent" species? We do not know. The only example we have is our own planet and it is difficult to say if our planet is extraordinarily special, or if it is just one of the planets with more than a trillion averages.
In addition, of the 5 intelligent species, only one (humans) is currently able to communicate with other planets, if we ever find someone to communicate with.
Therefore, the answer to your question is "We do not know".
Certainly we have not found any. But that does not prove that it can not exist.