A3. Our Buddha rediscovered the nibbana (Nirvana) and manifested the Dhamma about 25 centuries ago, and predicted the teachings will last not more than 5000 years. Actually, we are at approximately the mid era of Buddhism. The next Buddha, by the name of Metteya will come only after millions of years.

For further reading see "Description of Kakusandha the 22nd Buddha" Suttantapitaka, Khuddakanikaya, Buddhavamsa.