Appendix 1. CENTRAL search strategy

#1 Parkinson Disease:TI,AB,KY

#2 Parkinson*:TI,AB,KY

#3 #1 OR #2

#4 MESH DESCRIPTOR Glucagon‐Like Peptide 1 EXPLODE ALL TREES WITH QUALIFIERS AA,AG

#5 ((glucagon like peptide* or GLP 1 or GLP1) ADJ3 (analog* or agonist*)):TI,AB,KY

#6 (exenatide or AC 2993 or ITCA 650):TI,AB,KY

#7 (liraglutide or NN 2211 or NN2211 or NNC 90 1170 or NNC90 1170):TI,AB,KY

#8 (albiglutide or GSK 716155):TI,AB,KY

#9 (elsiglutide):TI,AB,KY

#10 (lixisenatide or AVE 0010):TI,AB,KY

#11 (dulaglutide or LY2189265 or LY 2189265):TI,AB,KY

#12 (taspoglutide or BIM 51077 or BIM51077 or ITM 077 or ITM077 or R 1583 or R1583 or RO 5073031 or RO5073031):TI,AB,KY

#13 (semaglutide or NN 9535 or NN9535):TI,AB,KY

#14 (teduglutide or ALX 0600 or ALX0600):TI,AB,KY

#15 OR/#4‐#14

#16 #3 and #15 in Trials

Appendix 2. MEDLINE search strategy

#1 randomized controlled trial.pt.

#2 controlled clinical trial.pt.

#3 randomized.ab.

#4 placebo.ab.

#5 clinical trials as topic.sh.

#6 randomly.ab.

#7 trial.ti.

#8 1 or 2 or 3 or 4 or 5 or 6 or 7

#9 animals.mh. not humans.mh.

#10 #8 not #9

#11 Parkinson Disease.mh.

#12 Parkinson*.ti,ab.

#13 #11 or #12

#14 exp Glucagon‐Like Peptide 1/aa,ag [Analogs & Derivatives, Agonists]

#15 ((glucagon like peptide* or GLP 1 or GLP1) adj3 (analog* or agonist*)).tw.

#16 (exenatide or AC 2993 or ITCA 650).tw.

#17 (liraglutide or NN 2211 or NN2211 or NNC 90 1170 or NNC90 1170).tw.

#18 (albiglutide or GSK 716155).tw.

#19 (elsiglutide).tw.

#20 (lixisenatide or AVE 0010).tw.

#21 (dulaglutide or LY2189265 or LY 2189265).tw.

#22 (taspoglutide or BIM 51077 or BIM51077 or ITM 077 or ITM077 or R 1583 or R1583 or RO 5073031 or RO5073031).tw.

#23 (semaglutide or NN 9535 or NN9535).tw.

#24 (teduglutide or ALX 0600 or ALX0600).tw.

#25 OR/14‐24

#26 #10 and #13 and #25

Appendix 3. EMBASE search strategy

#1 random$.tw.

#2 clinical trial:.mp.

#3 placebo$.mp.

#4 double‐blind$.tw.

#5 1 or 2 or 3 or 4

#6 Parkinson*.ti,ab.

#7 Parkinson Disease/exp

#8 6 or 7

#9 ((glucagon like peptide* or GLP 1 or GLP1) adj3 (analog* or agonist*)).tw.

#10 (exenatide or AC 2993 or ITCA 650).tw.

#11 (liraglutide or NN 2211 or NN2211 or NNC 90 1170 or NNC90 1170).tw.

#12 (albiglutide or GSK 716155).tw.

#13 (elsiglutide).tw.

#14 (lixisenatide or AVE 0010).tw.

#15 (dulaglutide or LY2189265 or LY 2189265).tw.

#16 (taspoglutide or BIM 51077 or BIM51077 or ITM 077 or ITM077 or R 1583 or R1583 or RO 5073031 or RO5073031).tw.

#17 (semaglutide or NN 9535 or NN9535).tw.

#18 (teduglutide or ALX 0600 or ALX0600).tw.

#19 or/9‐37

#20 5 and 8 and 19