Penwest Pharmaceuticals (PPCO) 10-K/A 2007 FY Annual report (amended)

Exhibit 31.4

CERTIFICATION

I, Benjamin L. Palleiko, in my capacity as principal financial officer of Penwest Pharmaceuticals Co., certify that:

1. I have reviewed this Amendment No. 1 on Form 10-K/A (“this report”) of Penwest Pharmaceuticals Co.; and

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.

Date: April 10, 2008	/s/ Benjamin L. Palleiko
	Benjamin L. Palleiko
	Senior Vice President, Corporate Development and Chief Financial Officer