UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of February 2022

Commission File Number 001-15170

GlaxoSmithKline plc

(Translation of registrant's name into English)

980 Great West Road, Brentford, Middlesex, TW8 9GS

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F . . . .X. . . . Form 40-F . . . . . . . .

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ____

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ____

GlaxoSmithKline plc (the 'Company')

Vesting of Performance Share Plan Awards

This notification sets out the vesting details of awards over Ordinary Shares and American Depositary Shares ('ADSs') made to Persons Discharging Managerial Responsibilities ('PDMRs') and their Persons Closely Associated ('PCAs') in 2019 under the GlaxoSmithKline 2017 Performance Share Plan ('PSP'), which were subject to relevant business performance conditions, and the subsequent sale of ordinary shares and ADSs to meet tax liabilities.  Awards were made in 2019 and the three-year performance period commenced on 1 January 2019 and ended on 31 December 2021.  The vested shares for the Executive Directors are now subject to an additional two-year vesting period.  

The performance measure vesting details for those PDMRs who received awards in 2019 are set out in the following table. 

		Outcome and Vesting Level
Portion of the Award	Measure and Outcome	% of maximum	% of award
1/3rd	Adjusted Free Cash Flow - For the three-year period, the Company achieved Adjusted Free Cash Flow calculated in accordance with the principles for the measure of £14.53bn, which is above the level of £13.20bn required for maximum vesting.  Adjustments to the original target and vesting schedule were communicated in the 2020 Annual Report and will be set out in the 2021 Annual Report.	100	33.33
1/3rd	Total Shareholder Return - For the three years ending 31 December 2021, the Company's Total Shareholder Return ranked 10th, which is below the threshold vesting level against a comparator group of 10 global pharmaceutical companies including GSK.	0	0
1/3rd	R&D New Products - For the three-year period, the Company achieved New Product sales calculated in accordance with the principles for the measure of £11.12bn, which is slightly below the level of £11.14bn required for 75% vesting.  The threshold vesting level was £10.02bn.	74	24.66
	Total vesting for 2019 award Lapsed	58 42	57.99

The notifications that follow are for awards made to PDMRs and their PCAs and detail the PSP conditional awards that vested, including dividends accrued, on 16 February 2022.  The balance of the award made to each PDMR and PCA has lapsed.

The closing prices of Ordinary Shares and of ADSs of GlaxoSmithKline plc on the vesting date were £15.76 and $43.39.

Transaction notification

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms E Walmsley
b)	Position/status	Chief Executive Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary Shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	274,480
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr I Mackay
b)	Position/status	Chief Financial Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary Shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	152,815
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Dr H Barron
b)	Position/status	Chief Scientific Officer and President, R&D
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The number of ADSs vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$0.00	146,831
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Dr H Barron
b)	Position/status	Chief Scientific Officer and President, R&D
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The sale of ADSs to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$43.3404	79,172
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	New York Stock Exchange (XNYS)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr R Connor
b)	Position/status	President, Vaccines and Global Health
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary Shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	119,780
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr R Connor
b)	Position/status	President, Vaccines and Global Health
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary Shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	56,297
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms D Conrad
b)	Position/status	Chief People Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Following the vesting on 16 February 2022 of awards granted in 2019 under the Company's 2017 Performance Share Plan, Ms Conrad will receive a cash payment of £126,710.48 less applicable tax withholding in respect of 8,006 notional ordinary shares.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	8,006
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr J Ford
b)	Position/status	SVP and General Counsel
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The number of ADSs vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$0.00	46,446
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr J Ford
b)	Position/status	SVP and General Counsel
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The sale of ADSs to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$43.3404	21,830
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	New York Stock Exchange (XNYS)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms S Jackson
b)	Position/status	SVP, Global Communications and CEO Office
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	8,006
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms S Jackson
b)	Position/status	SVP, Global Communications and CEO Office
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	3,763
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr D Jackson
b)	Position/status	PCA of Ms S Jackson (SVP, Global Communications and CEO Office)
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	3,780
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr D Jackson
b)	Position/status	PCA of Ms S Jackson (SVP, Global Communications and CEO Office)
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	1,777
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr B McNamara
b)	Position/status	CEO, GSK Consumer Healthcare
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The number of ADSs vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$0.00	67,075
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr B McNamara
b)	Position/status	CEO, GSK Consumer Healthcare
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The sale of ADSs to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$43.3404	33,974
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	New York Stock Exchange (XNYS)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr L Miels
b)	Position/status	Chief Commercial Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	134,163
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr L Miels
b)	Position/status	Chief Commercial Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	4,008
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms S Ramakrishnan
b)	Position/status	Chief Technology and Digital Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The number of ADSs vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$0.00	4,558
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms S Ramakrishnan
b)	Position/status	Chief Technology and Digital Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	American Depositary Shares ('ADSs') ISIN: US37733W1053
b)	Nature of the transaction	The sale of ADSs to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			$43.3404	2,444
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	New York Stock Exchange (XNYS)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr D Redfern
b)	Position/status	Chief Strategy Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	110,567
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr D Redfern
b)	Position/status	Chief Strategy Officer
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	51,967
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr R Simard
b)	Position/status	President, Pharmaceuticals Supply Chain
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	64,497
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr R Simard
b)	Position/status	President, Pharmaceuticals Supply Chain
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	30,314
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr P Thomson
b)	Position/status	President, Global Affairs
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	50,497
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr P Thomson
b)	Position/status	President, Global Affairs
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	23,734
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms D Waterhouse
b)	Position/status	CEO, ViiV Healthcare
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	10,978
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms D Waterhouse
b)	Position/status	CEO, ViiV Healthcare
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	5,160
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms V Whyte
b)	Position/status	Company Secretary
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The number of Ordinary Shares vesting on awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£0.00	8,006
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	N/A

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms V Whyte
b)	Position/status	Company Secretary
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	The sale of Ordinary Shares to meet tax liabilities for the vesting of awards granted in 2019 under the Company's 2017 Performance Share Plan.
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£15.8269	3,763
d)	Aggregated information	N/A (single transaction)
	Aggregated volume Price
e)	Date of the transaction	2022-02-16
f)	Place of the transaction	London Stock Exchange (XLON)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorised.

	GlaxoSmithKline plc
	(Registrant)
Date: February 18, 2022
	By:/s/ VICTORIA WHYTE --------------------------
	Victoria Whyte
	Authorised Signatory for and on
	behalf of GlaxoSmithKline plc