<PAGE>   1
                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-Q

  X      Quarterly report pursuant to Section 13 or 15(d) of the Securities
 ---     Exchange Act of 1934.

         For the quarterly period ended June 30, 2000

         Transition report pursuant to Section 13 or 15(d) of the Securities
 ---     Exchange Act of 1934.

         For the transition period from ___________ to _________.

                             Commission File Number
                                  0 19777 10 1

                            ALLOS THERAPEUTICS, INC.
             (Exact name of Registrant as specified in its charter)

         DELAWARE                                               54-1655029
(State or other jurisdiction of                              (I.R.S. Employer
incorporation or organization)                               Identification No.)

                         7000 NORTH BROADWAY, SUITE 400
                             DENVER, COLORADO 80221
                                 (303) 426-6262
              (Address, including zip code, and telephone number,
              including area code, of principal executive offices)

     Indicate by check mark whether the Registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.

Yes  [X]         No   [ ]

     As of June 30, 2000, there were 22,838,655 shares of the Registrant's
Common Stock outstanding, par value $0.001 per share.


 This quarterly report on Form 10-Q, including exhibits, consists of 14 pages.
                    The exhibit index is located on page 14


<PAGE>   2

                            ALLOS THERAPEUTICS, INC.
                                   FORM 10-Q

                                     INDEX

<TABLE>
<CAPTION>

                                                                                              PAGE
                                                                                             NUMBER
                                                                                             ------
<S>                                                                                          <C>
PART I.  Financial Information

     ITEM 1.      Financial Statements ......................................................... 3

                  Balance Sheet --
                      as of June 30, 2000 (unaudited) and December 31, 1999 .................... 3

                  Statement of Operations (unaudited) --
                      for the three and six months ended June 30, 2000 and 1999 and the period
                      from inception (September 1, 1992) through June 30, 2000 ................. 4

                  Statement of Cash Flows (unaudited) --
                      for the six months ended June 30, 2000 and 1999 and the period from
                      inception (September 1, 1992) through June 30, 2000 ...................... 5

                  Notes to Financial Statements (unaudited) .................................... 6

     ITEM 2.      Management's Discussion and Analysis of Financial Condition and Results of
                  Operations ................................................................... 7

PART II.  Other Information ....................................................................12

     ITEM 1.      Legal Proceedings ............................................................12
     ITEM 2.      Changes in Securities and Use of Proceeds ....................................12
     ITEM 3.      Defaults Upon Senior Securities ..............................................12
     ITEM 4.      Submission of Matters to a Vote of Security Holders ..........................12
     ITEM 5.      Other Information ............................................................12
     ITEM 6.      Exhibits and Reports on Form 8-K .............................................12

SIGNATURES .....................................................................................13
</TABLE>


                                                                   Page 2 of 14


<PAGE>   3

                         PART I. FINANCIAL INFORMATION

ITEM 1.  FINANCIAL STATEMENTS

                            ALLOS THERAPEUTICS, INC.
                         (A DEVELOPMENT STAGE COMPANY)
                                 BALANCE SHEET

<TABLE>
<CAPTION>

                                                                                       JUNE 30,        DECEMBER 31,
                                      ASSETS                                            2000                1999
                                                                                    -------------      -------------
                                                                                     (unaudited)
<S>                                                                                 <C>                <C>
Current assets:
   Cash and cash equivalents                                                        $   1,158,500      $   2,597,884
   Short-term investments                                                              43,935,775          6,877,303
   Prepaid expenses - research                                                            677,934            223,117
   Prepaid expenses - other                                                                90,244             45,311
   Other assets                                                                             6,176            185,898
                                                                                    -------------      -------------
          Total current assets                                                         45,868,629          9,929,513
                                                                                    -------------      -------------
Marketable securities
                                                                                       43,743,353                 --
Property and equipment (net of accumulated depreciation of $386,613 and
      $322,227, respectively)                                                             235,945            230,360
Other assets                                                                               23,979             45,641
                                                                                    -------------      -------------
          Total assets                                                              $  89,871,906      $  10,205,514
                                                                                    =============      =============
                       LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
   Accounts payable - related parties                                               $       5,072      $       8,087
   Accrued expenses - research                                                          1,071,648            768,592
   Accounts payable - trade                                                               199,805             65,123
   Accrued compensation and employee benefits                                             177,325            224,379
   Current portion of capital lease obligations                                            66,590             79,042
                                                                                    -------------      -------------
          Total current liabilities                                                     1,520,440          1,145,223
Long-term portion of capital lease obligations                                             37,728             69,320
                                                                                    -------------      -------------
          Total liabilities                                                             1,558,168          1,214,543

Stockholders' equity:
   Convertible preferred stock, Series A: $0.001 par value, 0 and 5,000,000
      shares authorized, issued and outstanding at June 30, 2000 and December
      31, 1999, respectively (liquidation value: $6,718,107 at December 31,
      1999)                                                                                    --              5,000
   Convertible preferred stock, Series B: $0.001 par value, 0 and 5,050,000
      shares authorized at June 30, 2000 and December 31, 1999, respectively; 0
      and 5,032,500 shares issued and outstanding at June 30, 2000 and December
      31, 1999, respectively (liquidation value: $10,191,261 at December 31,
      1999)                                                                                    --              5,033
   Convertible preferred stock, Series C: $0.001 par value, 0 and 16,610,000
      shares authorized at June 30, 2000 and December 31, 1999, respectively; 0
      and 15,255,786 shares issued and outstanding at June 30, 2000 and
      December 31, 1999, respectively (liquidation value: $30,161,846 at
      December 31, 1999)                                                                       --             15,256
   Preferred stock, $0.001 par value; 10,000,000 shares authorized at June 30,
      2000, no shares issued or outstanding                                                    --                 --
   Common stock, $0.001 par value; 75,000,000 and 31,000,000 shares authorized
      at June 30, 2000 and December 31, 1999, respectively; 22,838,655 and
      2,022,138 shares issued and outstanding at June 30, 2000 and December 31,
      1999, respectively                                                                   22,839              2,022
Additional paid-in capital preferred stock                                                     --         49,873,495
Additional paid-in capital common stock                                               156,521,815          7,020,291
Notes receivable - related parties                                                        (49,687)          (139,687)
Accumulated deficit                                                                   (58,154,258)       (43,348,145)
Deferred compensation related to grant of options                                     (10,026,971)        (4,442,294)
                                                                                    -------------      -------------
          Total stockholders' equity                                                   88,313,738          8,990,971
                                                                                    -------------      -------------
               Total liabilities and stockholders' equity                           $  89,871,906      $  10,205,514
                                                                                    =============      =============
</TABLE>


   The accompanying notes are an integral part of these financial statements.


                                                                   Page 3 of 14
<PAGE>   4


                            ALLOS THERAPEUTICS, INC.
                         (A DEVELOPMENT STAGE COMPANY)
                            STATEMENT OF OPERATIONS
                                  (UNAUDITED)


<TABLE>
<CAPTION>

                                                                                                                CUMULATIVE
                                                                                                                PERIOD FROM
                                                                                                             SEPTEMBER 1, 1992
                                                                                                                (INCEPTION)
                                                   THREE MONTHS ENDED                SIX MONTHS ENDED             THROUGH
                                                         JUNE 30,                        JUNE 30,                 JUNE 30,
                                                   2000            1999            2000            1999             2000
                                               ------------    ------------    ------------    ------------  -----------------
<S>                                            <C>             <C>             <C>             <C>           <C>
Operating expenses:
      Research and development                 $  2,033,409    $  2,401,676    $  5,880,026    $  4,378,983    $ 28,825,913
      Clinical manufacturing                        801,866         268,157       1,146,844         676,331       6,311,677
      General and administrative                  1,960,520         360,455       9,361,026         788,222      16,531,759
                                               ------------    ------------    ------------    ------------    ------------

          Total operating expenses                4,795,795       3,030,288      16,387,896       5,843,536      51,669,349

Loss from operations                             (4,795,795)     (3,030,288)    (16,387,896)     (5,843,536)    (51,669,349)
Interest and other income, net                    1,466,430          60,382       1,581,783         155,478       3,128,066
                                               ------------    ------------    ------------    ------------    ------------

            Net loss                             (3,329,365)     (2,969,906)    (14,806,113)     (5,688,058)    (48,541,283)

Dividend related to beneficial conversion
feature of preferred stock                               --              --              --              --      (9,612,975)
                                               ------------    ------------    ------------    ------------    ------------
Net loss attributable to common stockholders   $ (3,329,365)   $ (2,969,906)   $(14,806,113)   $ (5,688,058)   $(58,154,258)
                                               ============    ============    ============    ============    ============
Net loss per common share:
      Basic and diluted                        $      (0.15)   $      (1.49)   $      (1.13)   $      (2.86)
                                               ============    ============    ============    ============

Weighted average common shares - basic and
   diluted                                       22,837,154       1,989,347      13,053,937       1,985,570
                                               ============    ============    ============    ============
</TABLE>



   The accompanying notes are an integral part of these financial statements.


                                                                   Page 4 of 14
<PAGE>   5

                            ALLOS THERAPEUTICS, INC.
                         (A DEVELOPMENT STAGE COMPANY)
                            STATEMENT OF CASH FLOWS
                                  (UNAUDITED)

<TABLE>
<CAPTION>

                                                                                                           CUMULATIVE
                                                                                                           PERIOD FROM
                                                                                                        SEPTEMBER 1, 1992
                                                                             SIX MONTHS ENDED          (INCEPTION) THROUGH
                                                                                  JUNE 30,                   JUNE 30,
                                                                             2000             1999             2000
                                                                        -------------    ------------- --------------------
<S>                                                                     <C>              <C>              <C>
Cash Flows From Operating Activities
      Net loss                                                          $ (14,806,113)   $  (5,688,058)   $ (48,541,283)
      Adjustments to reconcile net loss to net cash used in
        operating activities:
      Depreciation and amortization                                            64,386           72,460          416,408
      Stock-based compensation expense                                     11,378,141               --       13,746,902
      Other                                                                        --               --           52,406
      Changes in operating assets and liabilities:
        Decrease (increase) in prepaids and other assets                     (298,366)         201,425         (798,333)
        (Increase) decrease in interest receivable on
          short-term investments                                           (1,422,230)          60,142       (1,516,722)
        Increase (decrease) in accounts payable -
          related parties                                                      (3,015)        (109,472)           5,072
        Increase (decrease) in accounts payable -
          research                                                            303,056          226,389        1,071,648
        Increase (decrease) in accounts payable - trade                       134,682          (66,628)         199,805
        Increase (decrease) in accrued compensation
          and employee benefits                                               (47,054)          13,294          177,325
                                                                        -------------    -------------    -------------
            Net cash used in operating activities                          (4,696,513)      (5,290,448)     (35,186,772)
                                                                        -------------    -------------    -------------
Cash Flows From Investing Activities
        Acquisition of property and equipment                                 (69,971)         (13,645)        (363,163)
        Purchase of investments                                           (86,184,509)      (3,941,734)    (134,121,687)
        Proceeds from maturities of investments                             6,804,914        9,810,297       47,959,281
                                                                        -------------    -------------    -------------
            Net cash provided by (used in) investing activities           (79,449,566)       5,854,918      (86,525,569)
                                                                        -------------    -------------    -------------
Cash Flows From Financing Activities
        Principal payments under capital leases                               (44,044)         (57,051)        (317,770)
        Proceeds from sale leaseback                                               --               --          120,492
        Proceeds from stockholder loan                                             --               --           12,000
        Repayment of stockholder loan                                              --               --          (12,000)
        Proceeds from issuance of convertible preferred
          stock, net of issuance costs                                         (2,503)         (28,788)      40,283,306
        Proceeds from issuance of common stock, net of
          issuance costs                                                   82,753,242              569       82,784,813
                                                                        -------------    -------------    -------------
            Net cash provided by (used in) investing
               activities                                                  82,706,695          (85,270)     122,870,841
                                                                        -------------    -------------    -------------
Net increase (decrease) in cash                                            (1,439,384)         479,200        1,158,500
Cash and cash equivalents, beginning of period                              2,597,884        1,656,546               --
                                                                        -------------    -------------    -------------
Cash and cash equivalents, end of period                                $   1,158,500    $   2,135,746    $   1,158,500
                                                                        =============    =============    =============
Supplemental Schedule of Noncash Operating and Financing
        Activities:
        Cash paid for interest                                                 27,890               --           37,890
        Issuance of stock in exchange for license
          agreement                                                                --               --           40,000
        Capital lease obligations incurred for purchase of
          property and equipment                                                   --            2,105          422,088
Issuance of stock in exchange for notes receivable                                 --               --          139,687
</TABLE>

   The accompanying notes are an integral part of these financial statements.


                                                                   Page 5 of 14
<PAGE>   6


                            ALLOS THERAPEUTICS, INC.
                         (A DEVELOPMENT STAGE COMPANY)
                         NOTES TO FINANCIAL STATEMENTS
                                  (UNAUDITED)

1.  BASIS OF PRESENTATION

     The accompanying unaudited financial statements of Allos Therapeutics,
Inc., referred to herein as the Company, we, us or our, have been prepared
pursuant to the rules and regulations of the Securities and Exchange Commission
("SEC"). Certain information and footnote disclosures normally included in
financial statements prepared in accordance with generally accepted accounting
principles have been condensed or omitted pursuant to such rules and
regulations. However, the Company believes that the disclosures are adequate to
make the information presented not misleading. The unaudited financial
statements included herein have been prepared on the same basis as the annual
financial statements and reflect all adjustments, which include only normal
recurring adjustments necessary for a fair presentation in accordance with
generally accepted accounting principles. The results for the six-month period
ended June 30, 2000 are not necessarily indicative of the results expected for
the full fiscal year. These financial statements should be read in conjunction
with the December 31, 1999 audited financial statements and the notes thereto
included in the Company's Form S-1 filed with the SEC on March 27, 2000.

     The Company has not generated any revenue to date and its activities have
consisted primarily of developing products, raising capital and recruiting
personnel. Accordingly, the Company is considered to be in the development
stage at June 30, 2000 as defined in Statement of Financial Accounting
Standards No. 7, "Accounting and Reporting by Development Stage Enterprises".

2.   EARNINGS PER COMMON SHARE

     Basic earnings per common share is computed using the weighted average
number of common shares outstanding during the period. Diluted earnings per
common share is computed using the weighted average number of common and
potential common shares outstanding during the period. Potential common shares
consist of stock options and warrants and have been excluded from the
computation of diluted earnings per common share because their effect was
anti-dilutive.



                                                                   Page 6 of 14
<PAGE>   7


ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
OF OPERATIONS

     The following Management's Discussion and Analysis of Financial Condition
and Results of Operations as well as information contained elsewhere in this
report, contains statements that constitute "forward-looking statements" within
the meaning of Section 27A of the Securities Act of 1933, as amended, and
Section 21E of the Securities Exchange Act of 1934, as amended. You can
identify these statements by forward-looking words such as "may," "will,"
"expect," "intend," "anticipate," "believe," "estimate," "plan," "could,"
"should" and "continue" or similar words. Actual results could differ
materially from those anticipated in these forward-looking statements. Factors
that could cause or contribute to such differences include, but are not limited
to, those mentioned in the discussion below and those described in the "Risk
Factors" discussion of our Registration Statement on Form S-1 filed with the
Securities and Exchange Commission. As a result, you should not place undue
reliance on these forward-looking statements. We do not intend to update or
revise these forward-looking statements to reflect future events or
developments.

OVERVIEW

     We are a pharmaceutical company focused on developing and commercializing
innovative small molecule drugs initially for improving cancer treatments. Our
lead product candidate is RSR13. RSR13 is a synthetic small molecule that
increases the release of oxygen from hemoglobin, the oxygen carrying protein
contained within red blood cells. We believe RSR13 can be used to improve
existing treatments for cancer and treat many diseases attributed to or
aggravated by tissue oxygen deprivation.

     To date, we have devoted substantially all of our resources to research
and clinical development. We have not derived any commercial revenues from
product sales, and we do not expect to receive product revenues for at least
the next several years. We have incurred significant operating losses since our
inception in 1992 and, as of June 30, 2000, had an accumulated deficit of
$58,154,258. There can be no assurance if or when we will become profitable. We
expect to continue to incur significant operating losses over the next several
years as we continue to incur increasing research and development costs, in
addition to costs related to clinical trials and manufacturing activities. We
expect that losses will fluctuate from quarter to quarter and that such
fluctuations may be substantial. Our achieving profitability depends upon our
ability, alone or with others, to successfully complete the development of our
product candidates, and obtain required regulatory clearances and successfully
manufacture and market our future products.

RESULTS OF OPERATIONS

Expenses

   Research and Development

     Research and development expenses were $2,033,000 for the three months
ended June 30, 2000 compared to $2,402,000 for the three months ended June 30,
1999, which represents a $369,000, or 15% decrease. For the six months ended
June 30, 2000 and 1999, research and


                                                                   Page 7 of 14
<PAGE>   8

development expenses were $5,880,000 and $4,379,000, respectively. Excluding
the impact of the non-cash charges comprising amortization of deferred
compensation expense and stock compensation expense (see "Non-cash Charges"
below for discussion of stock compensation expense allocated to research and
development), research and development expenses decreased $1,879,000, or 43%.
The decrease in both periods was primarily due to lower clinical trial costs
resulting from the completion of several Phase II clinical trials in oncology
and cardiopulmonary bypass and the Phase III oncology trial just commencing.

   Clinical Manufacturing

     Clinical manufacturing expenses include the cost of manufacturing RSR13 for
use in clinical trials and costs associated with the scale-up of manufacturing
to support commercial requirements. Clinical manufacturing expenses increased to
$802,000 for the three months ended June 30, 2000 from $268,000 for the three
months ended June 30, 1999, which represents a $534,000, or 199% increase. For
the six months ended June 30, 2000 and 1999, clinical manufacturing expenses
were $1,147,000 and $676,000, respectively, which represents a $471,000
increase, or 70%. The increase in both periods was primarily related to
purchasing additional drug to meet expected clinical trial requirements
associated with our Phase III oncology trial and increased personnel cost.

   General and Administrative

     General and administrative expenses increased to $1,961,000, or 445% for
the three months ended June 30, 2000, from $360,000 for the three months ended
June 30, 1999. Excluding the impact of the non-cash charges (see "Non-cash
Charges" below for discussion of stock compensation expense allocated to general
and administrative), general and administrative expenses increased $484,000, or
134%. For the six months ended June 30, 2000 and 1999, general administrative
expenses were $9,361,000 and $788,000, respectively. Excluding the impact of the
non-cash charges, general and administrative expenses increased $649,000, or
82%. The increase in both periods was the result of an increase in headcount and
additional expenses associated with becoming a public company.

   Non-cash Charges

     For the three months and six months ended June 30, 2000, we recorded
amortization of deferred stock compensation of $1,753,000 and $3,671,000,
respectively. The compensation charge resulted from granting of certain options
to employees prior to our March 2000 initial public offering with exercise
prices below the fair market value of our common stock on their respective
grant dates. Of the $1,753,000 recorded for the three months ended June 30,
2000, $1,116,000 related to general and administrative, $573,000 related to
research and development and the remaining $64,000 related to clinical
manufacturing. For the six months ended June 30, 2000, $2,422,000 related to
general and administrative, $1,145,000 related to research and development and
$104,000 was clinical manufacturing.

     For the six months ended June 30, 2000, we recorded $7,617,000 in stock
compensation expense in connection with the forgiveness of the 1996 Notes (as
defined below) in the first


                                                                   Page 8 of 14
<PAGE>   9

quarter of 2000. Of this amount, $5,417,000 related to general and
administrative and the remaining $2,200,000 related to research and
development. This compensation charge is a result of obtaining recourse notes
receivable in March 1996 (the "1996 Notes") from two officers in the amount of
$90,000 upon the officers' exercise of 558,000 stock options. The 1996 Notes
accrued interest at 8% annually with interest and principal originally due
March 1998. In December 1997, the maturity dates for the 1996 Notes were
extended by two years and extended by an additional year in January 2000. Upon
forgiveness of the notes in March 2000, we recorded stock compensation expense
based on the difference between the fair market value of the underlying common
stock and option exercise price.

   Interest and Other Income, Net

     Interest income, net of interest expense, was $1,466,000 and $60,000 for
the three months ended June 30, 2000 and 1999, respectively, representing an
increase of $1,406,000, or 2,343%. For the six months ended June 30, 2000 and
1999, net interest income was $1,582,000 and $155,000, respectively,
representing an increase of $1,427,000, or 917%. These increases were primarily
attributable to increased earnings from higher investment balances resulting
from the proceeds of our initial public offering of common stock completed in
March 2000.

LIQUIDITY AND CAPITAL RESOURCES

     Our principal source of working capital has been private and public
equity financings as well as grant revenues and interest income.

     As of June 30, 2000, we had approximately $88,838,000 in cash, cash
equivalents and investments. Net cash used in operating activities of
$4,697,000 during the six months ended June 30, 2000 resulted primarily from
the net loss for the period and a reduction in accounts payable. Net cash used
in operating activities of $5,290,000 during the six months ended June 30, 1999
resulted primarily from the net loss for the period.

     Net cash used in investing activities of $79,450,000 for the six months
ended June 30, 2000, consisted primarily of purchases of investments net of
proceeds. Net cash provided by investing activities of $5,855,000 for the six
months ended June 30, 1999, consisted primarily of proceeds from the sale of
investments, net of purchases.

     Net cash provided by financing activities of $82,707,000 for the six
months ended June 30, 2000 primarily resulted from the sale of common stock
which was offset by payments under our capital lease obligations. Net cash used
in financing activities of $85,000 for the six months ended June 30, 1999,
consisted of payments under our capital lease obligations.

     Based upon the current status of our product development and
commercialization plans, we believe cash, cash equivalents and investments will
be adequate to satisfy our capital needs through at least the calendar year
2002. However, our actual capital requirements will depend on many factors,
including the status of product development; the time and cost involved in
conducting clinical trials and obtaining regulatory approvals; filing,
prosecuting and enforcing patent claims; competing technological and market
developments; and our ability to market and distribute our future products and
establish new collaborative and licensing arrangements.

                                                                   Page 9 of 14
<PAGE>   10

     Our forecast of the period of time through which our financial resources
will be adequate to support our operations is a forward-looking statement that
involves risks and uncertainties, and actual results could vary materially. The
factors described above will impact our future capital requirements and the
adequacy of our available funds. We may be required to raise additional funds
through public or private financings, collaborative relationships or other
arrangements. There can be no assurance that such additional funding, if
needed, will be available on terms attractive to us, or at all. Furthermore,
any additional equity financing may be dilutive to existing stockholders and
debt financing, if available, may involve restrictive covenants. Collaborative
arrangements, if necessary to raise additional funds, may require us to
relinquish rights to certain of our technologies, products or marketing
territories. Our failure to raise capital when needed could have a material
adverse effect on our business, financial condition and results of operations.

MARKET RISK

     We are exposed to certain market risks, primarily changes in interest
rates. Uncertainties that are either nonfinancial or nonquantifiable, such as
political, economic, tax, other regulatory, or credit risks, are not included
in the following assessment of our market risks.

     Investments, including cash equivalents, short-term investments and
long-term marketable securities, consist of commercial paper and corporate
bonds, with maturities of up to 24 months. All investments are classified as
held-to-maturity as defined in SFAS No. 115, "Accounting for Certain
Investments in Debt and Equity Securities," and accordingly are carried at
amortized costs. Changes in interest rates could impact our anticipated
interest income.

     We prepared sensitivity analyses of our interest rate exposures and its
exposure from anticipated investment for fiscal 2000 and 2001 to assess the
impact of hypothetical changes in interest rates. Based on the results of these
analyses, a 10% adverse change in interest rates from the 1999 fiscal year-end
rates would not have a material adverse effect of the fair value of investments
and would not materially impact our results of operations, cash flows, or
financial condition for the next twelve months.

RISK FACTORS

     In addition to the other information contained in this report, we caution
stockholders and potential investors that the following important factors,
among others, in some cases have affected, and in the future could affect, our
actual results of operations and could cause our actual results to differ
materially from those expressed in any forward-looking statements made by, on,
or on behalf of us. The following information is not intended to limit in any
way the characterization of other statements or information under other
captions as cautionary statements for such purpose. These factors include:

         o        Delay, difficulty, or failure to obtain regulatory approval
                  or clearance to market our product candidates; including
                  delays or difficulties in development because of insufficient
                  proof of safety or efficacy.

         o        Our limited experience in conducting and managing clinical
                  trials; failure to conduct clinical trials in compliance with
                  applicable regulations and at an acceptable cost.

                                                                   Page 10 of 14
<PAGE>   11

         o        The ability to obtain, maintain and enforce intellectual
                  property rights; the cost of acquiring in-process technology
                  and other intellectual property rights, either by license,
                  collaboration or purchase of another entity; the cost of
                  enforcing or defending our intellectual property rights.

         o        Failure of third party collaborators to conduct research and
                  development activities, including drug discovery and clinical
                  testing; conflicts of interest or priorities that may arise
                  between us and such third party collaborators.

         o        Dependence upon third parties to manufacture RSR13 bulk drug
                  substance and formulated drug product; failure of third
                  parties to manufacture RSR13 bulk drug substance or
                  formulated drug product in compliance with regulatory
                  requirements and at an acceptable cost; failure of third
                  parties to supply sufficient quantities of RSR13 bulk drug
                  substance or formulated drug product for preclinical,
                  clinical or commercial purposes; failure to establish
                  alternative sources of supply of RSR13 bulk drug substance or
                  formulated drug product.

         o        The ability to create sales, marketing and distribution
                  capabilities for our product candidates, or enter into
                  agreements with third parties to perform these functions;

         o        The ability to obtain acceptable prices or adequate levels of
                  reimbursement for our products from third party payors,
                  including government and health administration authorities
                  and private health insurers.

         o        Difficulties or high cost of obtaining adequate financing to
                  fund future research, development and commercialization of
                  product candidates.

         o        Competitive or market factors that may limit the use or broad
                  acceptance of our product candidates.

         o        The ability to attract and retain highly qualified management
                  and scientific personnel.

                                                                   Page 11 of 14

<PAGE>   12

                           PART II. OTHER INFORMATION
<TABLE>


<S>          <C>                                                                                     <C>
Item 1.      Legal Proceedings                                                                       None

Item 2.      Changes in Securities and Use of Proceeds

                 None

                 Report of Use of Proceeds from Initial Public Offering in March 2000:

                         Aggregate offering price                             $  90,000,000

                         Expenses incurred in connection with offering            7,300,000
                                                                              -------------

                         Net offering proceeds to issuer                         82,700,000

                         Investment in marketable securities                     82,700,000

Item 3.      Defaults Upon Senior Securities                                                         None

Item 4.      Submission of Matters to a Vote of Security Holders                                     None

Item 5.      Other Information                                                                       None

Item 6.      Exhibits and Reports on Form 8-K
                 (a)     Exhibits
                 (b)     Reports on Form 8-K                                                         27 (Financial Data Schedule)

                                                                                                     None
</TABLE>


                                                                   Page 12 of 14
<PAGE>   13

                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, as amended, (the "Exchange Act") the registrant has duly
caused this report to be signed on its behalf by the undersigned, thereunto
duly authorized.


Date:  July 26, 2000                       ALLOS THERAPEUTICS, INC.





                                           /s/ Stephen J. Hoffman
                                           -------------------------------------
                                           Stephen J. Hoffman, PhD, MD
                                           President and Chief Executive Officer



                                           /s/ Michael E. Hart
                                           -------------------------------------
                                           Michael E. Hart
                                           Chief Financial Officer and
                                           Sr. Vice President, Operations



                                           /s/ Paulette M. Wilson
                                           -------------------------------------
                                           Paulette M. Wilson
                                           Controller


                                                                   Page 13 of 14
<PAGE>   14

                                 EXHIBIT INDEX

<TABLE>
<CAPTION>

EXHIBIT
NUMBER          DESCRIPTION
------          -----------
<S>             <C>
27              FINANCIAL DATA SCHEDULE
</TABLE>



                                                                   Page 14 of 14