Exhibit 99

Joint Filing Information

Name: Barry Kurokawa

Address:	125 Cambridgepark Drive
	Cambridge, MA 02140

Designated Filer: David B. Musket

Issuer and Ticker Symbol: Aerogen Inc.	AEGN

Date of Event Requiring Filing:	July 28, 2005

Signature:	Barry Kurokawa
	By: /s/Barry Kurokawa

Date: August 17, 2005

Joint Filing Information

Name: ProMed Asset Management, L.L.C.

Address:	125 Cambridgepark Drive
	Cambridge, MA 02140

Designated Filer: David B. Musket

Issuer and Ticker Symbol: Aerogen Inc.	AEGN

Date of Event Requiring Filing:	July 28, 2005

Signature:

ProMed Asset Management, L.L.C.

By: /s/David B. Musket

Date: August 17, 2005

Joint Filing Information

Name: ProMed Partners, L.P.

Address:	125 Cambridgepark Drive
	Cambridge, MA 02140

Designated Filer: David B. Musket

Issuer and Ticker Symbol: Aerogen Inc.	AEGN

Date of Event Requiring Filing:	July 28, 2005

Signature:

ProMed Partners, L.P.

By: ProMed Asset Management, L.L.C., its general partner

By: /s/ David B. Musket

Date: August 17, 2005

Joint Filing Information

Name: ProMed Partners II, L.P.

Address:	125 Cambridgepark Drive
	Cambridge, MA 02140

Designated Filer: David B. Musket

Issuer and Ticker Symbol: Aerogen Inc.	AEGN

Date of Event Requiring Filing:	July 28, 2005

Signature:

ProMed Partners II, L.P.

By: ProMed Asset Management, L.L.C., its general partner

By: /s/ David B. Musket

Date: August 17, 2005

Joint Filing Information

Name: ProMed Management, Inc.

Address:	125 Cambridgepark Drive
	Cambridge, MA 02140

Designated Filer: David B. Musket

Issuer and Ticker Symbol: Aerogen Inc.	AEGN

Date of Event Requiring Filing:	July 28, 2005

Signature:	ProMed Management, Inc.
	By: /s/ David B. Musket

Date: August 17, 2005

Joint Filing Information

Name: ProMed Offshore Fund, Ltd.

Address: [TO BE INSERTED]

Designated Filer: David B. Musket

Issuer and Ticker Symbol: Aerogen Inc.	AEGN

Date of Event Requiring Filing:	July 28, 2005

Signature:	ProMed Offshore Fund, Ltd.
	By: /s/ David B. Musket, its [Director]

Date: August 17, 2005

Joint Filing Information

Name: ProMed Offshore Fund II, Ltd.

Address: [TO BE INSERTED]

Designated Filer: David B. Musket

Issuer and Ticker Symbol: Aerogen Inc.	AEGN

Date of Event Requiring Filing:	July 28, 2005

Signature:	ProMed Offshore Fund II, Ltd.
	By: /s/ David B. Musket, its [Director]

Date: August 17, 2005

AEROGEN INC 4