There are near hundred of such systems developed or in developement, of all them Drozd was the first actually developed and fielded, back in the 70s. Analogous in characteristics Trophy was deployed only recently, it is nothing special in this field.There are several active protection systems in development and testing:
Arena - KMB (Russia)
LEDS-150 - Saab (Sweden)
Iron Fist - IMI (Israel)
KAPS - ADD (S.Korea)
MAPS - Diehl, IMI (Germany/Israel)
AWiSS - Diehl (Germany)
Quick Kill - Raytheon (US)
AMAP-ADS - IBD (Germany)
But only Trophy is operational. And now its employed on entire brigade.
These pictures show how innefective Merkava's "modular composite armour" is, as compared to old T-72 with Kontakt. The armour module falls apart after a single cumulative hit (RPG or ATGM warhead), leaving rather huge vulnerable zone.