Isis Reports Financial Results and Highlights for First Quart...($26426 $20987 As reported loss fr...),Health

As reported loss from operations according to GAAP $(8,831) $(20,901)

Excluding compensation expense related to stock

options pursuant to SFAS 123(R) (3,759) (2,364)

Proforma loss from operations $(5,072) $(18,537)

Reconciliation of GAAP to Pro Forma Basis

As illustrated in the Selected Financial Information in this press release, pro forma operating expenses and pro forma loss from operations were adjusted from GAAP to exclude compensation expense related to stock options, which are non-cash. Isis has regularly reported non-GAAP measures for operating expenses and loss from operations as pro forma results. These measures are provided as supplementary information and are not a substitute for financial measures calculated in accordance with GAAP. Isis reports these pro forma results to better enable financial statement users to assess and compare its historical performance and project its future operating results and cash flows. Further, the presentation of Isis' pro forma results is consistent with how Isis' management internally evaluates the performance of its operations.

Ibis Biosciences, Inc.

Statements of Operations

(In Thousands)

Three months ended,

March 31,

2008 2007

(unaudited)

Revenue:

Commercial revenue(1) $1,195 $ 631

Research and development revenue under

collaborative agreements 1,784 945

Total revenue 2,979 1,576