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                                                                    EXHIBIT 10.6

                        Corcept Therapeutics Incorporated

                      PROMISSORY NOTE AND PLEDGE AGREEMENT

                    This Note contains an acceleration clause
                    -----------------------------------------

                                                        Date:   October 22, 2001

                                                          Menlo Park, California

Principal Amount:                   $187,250.00
                 ----------------------------------------------------------

Borrower:                           Robert L. Roe
         ------------------------------------------------------------------

Borrower's Spouse:                  Sara Jane Roe
                  ---------------------------------------------------------

Borrower's Residence:         c/o Corcept Therapeutics
                                      Incorporated
                                275 Middlefield Road
                     ------------------------------------------------------

                               Menlo Park, CA  94025
                     ------------------------------------------------------

         1.       Promise to pay.

         FOR VALUE RECEIVED, Borrower (jointly and severally with Borrower's
Spouse, if applicable) promises to pay to Corcept Therapeutics Incorporated, a
Delaware corporation (the "Company"), or the holder hereof, at the offices of
the Company at 275 Middlefield Road, Suite A, Menlo Park, California 94025, or
at such other place as the Company or such holder may designate in writing, the
Principal Amount shown above, together with unpaid and accrued interest,
pursuant to the terms and provisions of this Promissory Note and Pledge
Agreement made and entered into as of the Date shown above (the "Promissory
Note").

         2.       Interest.

         Interest shall accrue during the term of this Promissory Note at the
rate of 6.50% per annum, compounded monthly and payable in arrears.

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         3.       Term and payment

         The outstanding principal together with all accrued interest shall be
due and payable in full upon the earlier of (i) October 1, 2011, (ii) the date
of termination of Borrower's status as an employee, director or consultant of
the Company, or (iii) the date on which the Shares described in paragraph 5 are
sold.

         4.       Prepayment; acceleration.

         4.1 Prepayment of principal, or any portion thereof, together with all
unpaid and accrued interest thereon, may be made at any time without penalty.
Payments shall be applied first to accrued interest and then to principal.

         4.2 If Borrower desires to sell some but not all of the Shares
described in paragraph 5, below, then as a condition to the Company's consent to
such sale Borrower shall pay to Company an amount of principal in the same
proportion to the Principal Amount as the shares sold are to the total Shares,
plus all interest accrued to the date of the sale.

         4.3 Notwithstanding any provision set forth above, the entire unpaid
principal sum of this Promissory Note, together with all unpaid and accrued
interest thereon, shall become immediately due and payable upon the occurrence
of the following:

                  (a) termination of Borrower's status as an employee, director
         or consultant of the Company;

                  (b) the commission of any act of bankruptcy by Borrower, the
         execution by Borrower of a general assignment for the benefit of
         creditors, the filing by or against Borrower of any petition in
         bankruptcy or any petition for relief under the provisions of the
         Federal Bankruptcy Act or any other state or federal law for the relief
         of debtors and the continuation of such petition without dismissal for
         a period of twenty (20) days or more, the appointment of a receiver or
         trustee to take possession of any property or assets of Borrower, or
         the attachment of or execution against any property or assets of
         Borrower; or

                  (c) any default of Borrower's obligations under this
         Promissory Note, including the failure to pay when due the amounts
         payable hereunder.

         5.       Pledge and Escrow of Shares.

As security for Borrower's obligations under the Promissory Note, Borrower
hereby pledges to the Company and delivers in escrow to the Secretary of the
Company (the "Escrow Holder"), in a form transferable for delivery, 250,000


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shares of Common Stock of the Company (the "Shares"), and such additional
property received or distributed in respect of the Shares (the Shares and such
additional property are collectively referred to as the "Pledged Collateral").
The certificate representing the Shares shall be accompanied by a duly executed
Assignment Separate From Certificate in the from attached hereto as Exhibit A.

         6.       Additional Security

As additional security for the obligations of Borrower (and Borrower's Spouse,
if applicable) to repay the Principal Amount and accrued interest, Borrower
shall deliver to Company a deed of trust, in form reasonably acceptable to the
Company, to real property owned by Borrower having an assessed value in excess
of the Principal Amount (the "Additional Security"). Borrower shall assist
Company in every reasonable way to record and perfect the security interest
transferred.

         7.       Rights in Pledged Shares.

So long as there shall exist no condition, event or act which, with notice and
lapse of time, would constitute a breach, default or an event of default of or
under, the Promissory Note, Borrower shall be entitled to exercise the voting
power with respect to the Shares.

         8.       Termination of Pledge and Escrow.

Upon payment in full of the Promissory Note, the Borrower shall be entitled to
the return of the Pledged Collateral and cancellation of the deed of trust on
the Additional Security.

         9.       Successor and Assigns.

This Promissory Note shall be binding upon and inure to the benefit of the
Company and its successors and assigns.

         10.      Attorneys' Fees.

In the event of any action to enforce payment of this Promissory Note, in
addition to all other relief, the prevailing party in such action shall be
entitled to its reasonable attorneys' fees and expenses.

         11.      Governing Law.

This Promissory Note shall be construed in accordance with the laws of the State
of California as applied to agreements among California residents entered into
and to be performed entirely within California.


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         12.      Amendment.

This Promissory Note shall be amended only with the written consent of both the
Company and Borrower.

         13.      Waivers.

Borrower hereby waives presentment, protest, demand, notice of dishonor, and all
other notices, and all defenses and pleas on the grounds of any extension or
extensions of the time of payments or the due dates of this Promissory Note, in
whole or in part, before or after maturity, with or without notice. No renewal
or extension of this Promissory Note, no release or surrender of any collateral
given as security for this Promissory Note, and no delay in enforcement of this
Promissory Note or in exercising any right or power hereunder, shall affect the
liability of Borrower.

         14.      Signatures.

         The Borrower (and Borrower's Spouse, if applicable) have executed this
Promissory Note as of the date first above written, intending to be legally
bound.

                                                    /s/ Robert L. Roe

                                                    ----------------------------
                                                     Robert L. Roe  ("Borrower")


                                                    /s/ Sara Jane Roe


                                                    ----------------------------
                                                     Borrower's Spouse

ACCEPTED AND ACKNOWLEDGED:

Corcept Therapeutics Incorporated

By:  /s/ Joseph K. Belanoff
    ----------------------------------------------------------

Printed name:   Joseph K. Belanoff
             -------------------------------------------------

Title:          Chief Executive Officer
      --------------------------------------------------------

Date:           October 22, 2001
     ---------------------------------------------------------



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                                    EXHIBIT A
                                    ---------

                                       to

                      Promissory Note and Pledge Agreement

                      ASSIGNMENT SEPARATE FROM CERTIFICATE

     FOR VALUE RECEIVED, Robert L. Roe. hereby sells, assigns and transfers
                         --------------
250,000 shares of Common Stock of Corcept Therapeutics Incorporated. (the
-------
"Company"), standing in the name of Robert L. Roe. on the books of said
                                    --------------
corporation represented by Certificate No. _____ and does hereby irrevocably
constitute and appoint the Corporate Secretary of the Company to transfer the
said stock on the books of the within named Company with full power of
substitution in the premises to the following:

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________




Dated:  ____________________.

                                           /s/ Robert L. Roe
                                      ------------------------------------------
                                      Robert L. Roe