No, it needs its leaves to ripen the fruit. If it's getting out of control, you might want to pinch the growing tips to slow the growth. Once the fruit is harvested, you can do a light pruning to keep it from grabbing passers by, but the main pruning should wait until just after Christmas.

If the fruit tends to be small, allow it to produce fewer clusters next year, and make sure the tub is big enough--at least 70 cm tall and wide. Some grape varieties will naturally produce small fruit unless they are treated with gibberellic acid, like the commercial growers do.