Although I couldn't find any Biostatistics course in Warsaw under a good university, it's better than nothing..
Here's a person from Warsaw who offers some 'Biostatistic' help for master's/doctoral dissertation - she might be interested:
olx.pl/oferta/biostatystyka-statystyka-medyczna-doktoraty-magisterki-licencjaty-CID619-ID4v5dP.html
You may also ask this person:
statmach.com/contact.html