Exhibit 4.5

SECOND SUPPLEMENTAL INDENTURE dated as of March 21, 2014, among GlaxoSmithKline Capital Inc., a corporation organized under the laws of the State of Delaware (the “Company”), GlaxoSmithKline plc, a public limited company incorporated under the laws of England and Wales, as guarantor (the “Guarantor”), and Law Debenture Trust Company of New York (as successor to Citibank, N.A.), a company duly organized and existing under the laws of the State of New York (the “Trustee”).

RECITALS

WHEREAS, the Company, the Guarantor and Citibank, N.A., a national banking association duly organized and existing under the laws of the United States (the “Former Trustee”), entered into an indenture, dated as of April 6, 2004 (as supplemented by the first supplemental indenture dated as of March 18, 2013, the “Indenture”), relating to the issuance from time to time by the Company of its Securities;

WHEREAS, the Company, the Guarantor, the Former Trustee and the Trustee entered into an Instrument of Resignation, Appointment and Acceptance, dated as of December 27, 2007, whereby the Former Trustee resigned as trustee, and the Trustee was appointed, and accepted its appointment, as trustee under the Indenture;

WHEREAS, Section 10.01 of the Indenture provides, among other things, that a supplemental indenture may be entered into by the Company, the Guarantor and the Trustee, without notice to or the consent of any Holders, (i) to establish the terms of Securities of any series; and/or (ii) to make any change that does not materially and adversely affect the rights of any Holder of Securities outstanding prior to the date of such supplemental indenture;

WHEREAS, the Company and the Guarantor have requested the Trustee to join with it in the execution and delivery of this second supplemental indenture (the “Second Supplemental Indenture”) in order to supplement and amend the Indenture, solely with respect to Securities issued on or after the date hereof, to: (1) amend certain redemption provisions and (2) amend a certain covenant of the Company and the Guarantor; in no event will the provisions of this Second Supplemental Indenture affect the interests of the Holders of Securities of any series outstanding prior to the date of this Second Supplemental Indenture in any respect;

WHEREAS, the Company and the Guarantor have determined that this Second Supplemental Indenture complies with said Section 10.01, does not affect the interests of any Holders of Securities outstanding prior to the date of this Second Supplemental Indenture and does not require notice to or the consent of any Holders; and

WHEREAS, the Company and the Guarantor represent and warrant that all things necessary to make this Second Supplemental Indenture a valid agreement of the Company, the Guarantor and the Trustee, in accordance with the terms of the Indenture, and a valid amendment of and supplement to the Indenture have been done;

NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH:

For and in consideration of the premises and the mutual covenants contained herein and in the Indenture and for other good and valuable consideration, the receipt and sufficiency of which are herein acknowledged, the Company, the Guarantor and the Trustee hereby agree, for the equal and ratable benefit of the Holders, as follows:

ARTICLE I

DEFINITIONS

SECTION 1.01 Defined Terms. All capitalized terms used but not defined herein shall have the meanings ascribed to such terms in the Indenture, as supplemented and amended hereby. All definitions in the Indenture shall be read in a manner consistent with the terms of this Second Supplemental Indenture.

SECTION 1.02 Additional Definitions.

“Additional Amounts” has the meaning specified in Section 4.05 of the Indenture.

ARTICLE II

AMENDMENTS TO THE INDENTURE

SECTION 2.01 Amendments to Section 3.01 Relating to Redemption. Section 3.01 of the Indenture is amended, with respect to Securities outstanding under series created on or after the date hereof, to read as follows:

“Section 3.01 Applicability of Article. Securities of any series that are redeemable before their maturity shall be redeemable in accordance with their terms and (except as otherwise specified as contemplated by Section 2.03 of the Indenture for Securities of any series) in accordance with this Article Three. The provisions of this Article Three shall be applicable to the Securities of any series, in whole but not in part, if, with respect to such series:

(a) the Company (or, if applicable, the Guarantor) determines that, as a result of any change in or amendment to the laws or any regulations or rulings promulgated thereunder of the United Kingdom (or of any political subdivision or taxing authority thereof) or the United States (or of any political subdivision or taxing authority thereof), or any change in the application or official interpretation of such laws, regulations or rulings, or any change in the application or official interpretation of, or any execution of or amendment to, any treaty or treaties affecting taxation to which any such jurisdiction is a party, which change, execution or amendment becomes effective on or after the issue date or such other date specified in the Securities of such series,

(i) the Company (or, if applicable, the Guarantor) would be required to pay Additional Amounts (as defined in Section 4.05) with respect to such series of Securities on the next succeeding interest payment date and the payment of such Additional Amounts cannot be avoided by the use of reasonable measures available to the Company or the Guarantor, or

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(ii) withholding tax has been or would be required to be withheld with respect to interest income received or receivable by the Company directly from the Guarantor (or any affiliate) and such withholding tax obligation cannot be avoided by the use of reasonable measures available to the Company or the Guarantor (or any affiliate); or

(b) the Company (or, if applicable, the Guarantor) determines, based upon an opinion of independent counsel of recognized standing that, as a result of any action taken by any legislative body of, taxing authority of, or any action brought in a court of competent jurisdiction, in the United Kingdom (or of any political subdivision or taxing authority thereof) or the United States (or of any political subdivision or taxing authority thereof) (whether or not such action was taken or brought with respect to the Company or the Guarantor), which action is taken or brought on or after the issue date or such other date specified in the Securities of such series, there is a substantial probability that the circumstances described in subsection (a) above would exist; provided, however, that no such notice of redemption may be given earlier than 90 days prior to the earliest date on which the Company would be obligated to pay such Additional Amounts. The Company or the Guarantor will also pay to each Holder, or make available for payment to each such Holder, on the redemption date any Additional Amounts resulting from the payment of such redemption price.”

ARTICLE III

SECTION 3.01 Amendments to Section 4.05 Relating to Payment of Additional Amounts. Section 4.05 of the Indenture is amended, with respect to Securities outstanding under series created on or after the date hereof, to read as follows:

“Section 4.05 Payment of Additional Amounts. All payments of Principal and interest in respect of the Securities shall be free and clear of and without withholding or deduction for or on account of any present or future tax, duty, levy, impost, assessment or other governmental charge of any nature whatsoever imposed or levied by or on behalf of (i) the government of the United Kingdom or of any territory of the United Kingdom or by any authority or agency therein or thereof having the power to tax or (ii) the government of the United States or of any state or territory of the United States or by any authority or agency therein or thereof having the power to tax (collectively, “Taxes”), except to the extent such Taxes are required to be withheld or deducted by law or by the interpretation or administration thereof. If either the Company or the Guarantor is so required to withhold or deduct any amount for or on account of Taxes from any payment made in respect of the Securities, the Company or the Guarantor, as the case may be, shall pay such additional amounts (“Additional Amounts”) as may be necessary such that the net amount received by each Holder (including such Additional Amounts) after such withholding or deduction shall not be less than the amount such Holder would have received if the Taxes had not been withheld or deducted; provided that no Additional Amounts will be payable with respect to Taxes:

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(a) that would not have been imposed but for the existence of any present or former connection between such Holder or beneficial owner of the Securities (or between a fiduciary, settlor, beneficiary, member or shareholder of, or possessor of a power over, such Holder or beneficial owner, if such Holder or beneficial owner is an estate, trust, partnership or corporation) and the United Kingdom or the United States or any political subdivision or territory or possession thereof or therein or area subject to its jurisdiction, including, without limitation, such Holder or beneficial owner (or such fiduciary, settlor, beneficiary, member, shareholder or possessor) being or having been a citizen or resident thereof or treated as a resident thereof or domiciled thereof or a national thereof or being or having been present or engaged in trade or business therein or having or having had a permanent establishment therein;

(b) that are estate, inheritance, gift, sales, transfer, personal property, wealth or similar taxes, duties, assessments or other governmental charges;

(c) that are payable other than by withholding from payments of Principal of or interest on the Securities;

(d) that would not have been imposed but for the failure of the applicable recipient of such payment to comply with any certification, identification, information, documentation or other reporting requirement to the extent such compliance is required by applicable law or administrative practice or an applicable treaty as a precondition to exemption from, or reduction in, the rate of deduction or withholding of such Taxes;

(e) that would not have been imposed but for the presentation of a Security (where presentation is required) for payment on a date more than 30 days after the date on which such payment became due and payable or the date on which payment thereof was duly provided for, whichever occurred later;

(f) that are imposed on a payment to an individual and are required to be made pursuant to European Council Directive 2003/48/EC or any other Directive implementing the conclusions of the ECOFIN Council meeting of November 26-27, 2000 on the taxation of savings income, or any law implementing or complying with, or introduced in order to conform to, such Directive;

(g) that would not have been imposed if presentation for payment of the relevant Securities had been made to a Paying Agent other than the Paying Agent to which the presentation was made;

(h) that are imposed solely by reason of the Holder or beneficial owner owning or having owned, actually or constructively, 10% or more of the total combined voting power of all classes of the Company’s stock entitled to vote;

(i) that would not have been imposed but for a failure by the Holder or beneficial owner (or any financial institution through which the Holder or beneficial owner holds any Security through which payment on the Security is made) to comply

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with any certification, information, identification, documentation or other reporting requirements (including entering into and complying with an agreement with the U.S. Internal Revenue Service or any other governmental authority) imposed pursuant to Sections 1471 through 1474 of the U.S. Internal Revenue Code as in effect on the date of issuance of the Notes or any successor or amended version of such provisions, any agreement entered into pursuant to Section 1471(b) of the U.S. Internal Revenue Code, or any fiscal or regulatory legislation, rules or practices adopted pursuant to any intergovernmental agreement entered into in connection with the implementation of such Sections of the U.S. Internal Revenue Code (or any law implementing such an intergovernmental agreement);”.

(j) any combination of the foregoing clauses (a) through (i);

nor shall Additional Amounts be paid with respect to any payment of the Principal of or interest on any Security to any such Holder who is a fiduciary or a partnership or a beneficial owner who is other than the sole beneficial owner of such payment to the extent a beneficiary or settlor with respect to such fiduciary or a member of such partnership or a beneficial owner would not have been entitled to such Additional Amounts had it been the Holder of the Security.

The Company shall maintain, in respect of Securities of each series outstanding, at least one Paying Agent located outside the United Kingdom. In the event that a Paying Agent with respect to Securities of a particular series is maintained in any member state of the European Union, the Company shall maintain a Paying Agent in at least one member state that will not be obliged to withhold or deduct taxes pursuant to any law implementing European Council Directive 2003/48/EC or any other Directive implementing the conclusions of the ECOFIN Council meeting of November 26-27, 2000 on the taxation of savings income, provided there is at least one member state that does not require a paying agent to withhold or deduct pursuant to such Directive.

The obligation of the Company or the Guarantor, as the case may be, to pay Additional Amounts if and when due will survive the termination of this Indenture and the payment of all amounts in respect of the Securities.”

ARTICLE IV

GENERAL PROVISIONS

SECTION 4.01 Trustee Makes No Representation. The recitals contained herein shall be taken as the statements of the Company and the Guarantor, and the Trustee assumes no responsibility for the correctness of same. The Trustee makes no representation as to the validity of this Second Supplemental Indenture.

SECTION 4.02 Effect of the Second Supplemental Indenture. This Second Supplemental Indenture supplements the Indenture and shall be a part, and subject to all the terms, thereof. The Indenture, as supplemented and amended by this Second Supplemental Indenture, is in all respects ratified and confirmed, and the Indenture and the Second Supplemental Indenture shall be

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read, taken and construed as one and the same instrument; provided, however, that any provision in this Second Supplemental Indenture which conflicts with any corresponding provision in the Indenture shall replace such conflicting terms in the Indenture in their entirety, to the extent that such terms relate to any Securities issued hereafter. All provisions included in this Second Supplemental Indenture supersede any conflicting provisions included in the Indenture unless not permitted by law.

SECTION 4.03 Counterparts. This Second Supplemental Indenture may be executed in any number of counterparts, each of which so executed shall be deemed to be an original, but all such counterparts shall together constitute but one and the same instrument.

SECTION 4.04 Trust Indenture Act. The Company and the Guarantor hereby certify that this Second Supplemental Indenture conforms to the current requirements of the Trust Indenture Act.

SECTION 4.05 Governing Law; Waiver of Jury Trial. The laws of the State of New York shall govern this Second Supplemental Indenture. Each of the Company, the Guarantor and the Trustee hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Second Supplemental Indenture.

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IN WITNESS WHEREOF, the parties hereto have caused this Second Supplemental Indenture to be duly executed, all as of the date first written above.

GLAXOSMITHKLINE CAPITAL INC., as Issuer
By:	/s/ Simon Dingemans
	Name: Simon Dingemans
	Title: President
GLAXOSMITHKLINE PLC, as Guarantor
By:	/s/ Simon Dingemans
	Name: Simon Dingemans
	Title: Chief Financial Officer
LAW DEBENTURE TRUST COMPANY OF NEW YORK, as Trustee
By:	/s/ James Heaney
	Name: James Heaney
	Title: Managing Director