August 22, 2018

Jennifer Burstein
Senior Vice President of Finance
Loxo Oncology, Inc.
281 Tresser Blvd
9th Floor
Stamford, CT 06901

       Re: Loxo Oncology, Inc.
           Form 10-K for the fiscal year ended December 31, 2017
           Filed March 1, 2018
           File No. 001-36562

Dear Ms. Burstein:

        We have limited our review of your filing to the financial statements
and related
disclosures and have the following comment. In our comment, we may ask you to
provide us
with information so we may better understand your disclosure.

       Please respond to this comment within ten business days by providing the
requested
information or advise us as soon as possible when you will respond. If you do
not believe our
comment applies to your facts and circumstances, please tell us why in your
response.

       After reviewing your response to this comment, we may have additional
comments.

Form 10-K for the fiscal year ended December 31, 2017

Financial Statements
Notes to the Financial Statements
3. Collaboration Agreement, page 76

1.    With regard to the $400 million non-refundable, upfront license fee
received in the
      agreement with Bayer and the estimates made in accounting for the
agreement, please tell
      us:
        more specifically what you mean by "Therefore, there was significant
judgment
          applied in determining a reasonable, rational method of recognizing
revenue under the
          Bayer Agreement, with the Company considering the guidance in ASC 606
Revenue
          from Contracts with Customers," and whether and, if so, to what
extent you
 Jennifer Burstein
Loxo Oncology, Inc.
August 22, 2018
Page 2
             analogized to ASC 606 or other literature and, if not, the basis
in the accounting
             literature for the accounting you applied to separate, allocate,
measure and recognize
             amounts within the collaborative arrangement,
             the amount allocated to each of larotrectinib and LOXO-195 and
your consideration of
             disclosing the amount allocated to each of larotrectinib and
LOXO-195 separately,
             how you determined the five years over which you will complete
development
             activities for larotrectinib when we note the FDA accepted a New
Drug Application on
             May 29, 2018,
             your basis in the accounting literature for recognizing milestone
payments when
             achieved addressing regulatory milestones separately from sales
milestones,
             why you record reimbursement for 50% of your development activity
expenses
             incurred as a reduction to research and development costs rather
than as part of the
             transaction price for purposes of recording revenue given your
accounting for research
             and development activities as a performance obligation that you
recognize using the
             proportional performance method,
             the basis in the accounting literature for presenting in 2018 the
co-promote loss as
             negative revenue rather than as an expense, and
             the breakout showing the amount and type of regulatory versus
sales milestone related
             to the $450 million in milestone payments upon larotrectinib
regulatory approvals and
             first commercial sale events in certain major markets and an
additional $200 million in
             milestone payments upon LOXO-195 regulatory approvals and first
commercial sale
             events in certain major markets.
       In closing, we remind you that the company and its management are
responsible for the
accuracy and adequacy of their disclosures, notwithstanding any review,
comments, action or
absence of action by the staff.

       You may contact Christine Torney at 202-551-3652 or Lisa Vanjoske at
202-551-3614
with any questions.



FirstName LastNameJennifer Burstein                           Sincerely,
Comapany NameLoxo Oncology, Inc.
                                                              Division of
Corporation Finance
August 22, 2018 Page 2                                        Office of
Healthcare & Insurance
FirstName LastName