FINAL

EXHIBIT 10.1

FINAL

FISCAL YEAR 2005 CEO BONUS PLAN

CEO

Up to 60% of CEO’s base salary.

The amount of Base Bonus Pool received will be calculated based on the following Performance Areas: Business Development, R&D Clinical Development, Sales & Marketing, Common Stock Performance and Corporate Finance. The relative weighting of each area has been determined by management and the Compensation Committee, and the total of all areas in Section 4 is equal to 70% of the Base Bonus Pool.

In addition up to 30% of the Base Bonus Pool will be allocated by the Nominating and Governance Committee of the Board of Directors based on the annual CEO Evaluation which will assess the CEO’s leadership skills and accomplishments.

—    All or a portion of this goal will be earned based on the higher of the formulas derived from either the (a) relative stock performance of Indevus’ Common Stock during the fiscal year or (b) the actual percentage increase in Indevus’ Common Stock during the fiscal year. Since achievement of a large increase in Indevus’ Common Stock either over an Index or over its price at the beginning of the fiscal year is beneficial to the Company’s shareholders, the calculation is made based on the higher one.

The Index is calculated based on the publicly available AMEX Biotechnology Index (or close equivalent if unavailable).

Due to the potential for short term news driven fluctuations in stock price, the average of the closing common stock price for the five trading days up to and including 9/30/04 and 9/30/05 will be used instead of the closing common stock price on that day.

This additional goal would be over and above any bonuses earned pursuant to Sections 2, 3, 4, 6, 7 and 8. In-license a second marketed product suitable for our existing sales force on terms approved by the Board of Directors. Achievement of this goal will result in a bonus of 20% of base salary.

This additional goal would be over and above any bonuses earned pursuant to Sections 2, 3, 4, 5, 6, 7 and 8. Out-license two existing compounds in our portfolio on terms approved by the Board of Directors. Achievement of this goal will result in a bonus of 20% of base salary.

This additional goal would be over and above any bonuses earned pursuant to Sections 2, 3, 4, 5, 7 and 8. Complete enrollment in the first Aminocandin Phase 2 trial. Achievement of this goal will result in a bonus of 20% of base salary.

This additional goal would be over and above any bonuses earned pursuant to Sections 2, 3, 4, 5, 6 and 8. Complete a transaction, on terms approved by the Board of Directors, that significantly enhances long-term shareholder value. Achievement of this goal will result in a bonus of 20-60% of base salary, at the discretion of the Compensation Committee.

This additional goal would be over and above any bonuses earned pursuant to Sections 2, 3, 4, 5, 6 and 7. Achieve gross sales of SANCTURA >105% of target. Achievement of this goal will result in a bonus of 20-30% of base salary at the discretion of the Compensation Committee.

A recommended calculation of the bonus will be made by management and will be reviewed and approved by the Compensation Committee. Bonuses may be paid periodically during the fiscal year upon attainment of goals, but not later than October 31, 2005. Payment will be made only to recipients who are still employees of the Company at the time of payment of the bonuses or October 31, 2005, whichever is earlier.