Peptide Library

Evidence

Human clinical vs. preclinical peptide research

Every counted publication has one evidence class, so the shares add up to 100% of classified publications. A study in people is not automatically better evidence, and a large animal literature says nothing about effects in people. How each class is decided is on the methodology page.
Automated weekly refresh (not editorially reviewed) · data through November 1, 2026 · version weekly-2026-11-01

The evidence mix

Share of publications that are human clinical research

37.8%

37.8% of classified peptide publications report human clinical research.

24,249 of 64,079

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Share of publications that are preclinical

39.0%

39.0% of classified peptide publications are animal, cell or computational studies.

25,022 of 64,079

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Share that are animal studies

27.8%

27.8% of classified peptide publications are animal studies.

17,799 of 64,079

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Share that are in vitro studies

10.0%

10.0% of classified peptide publications are in vitro studies.

6,427 of 64,079

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Share that are reviews and meta-analyses

16.5%

16.5% of classified peptide publications are reviews or meta-analyses.

10,563 of 64,079

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Randomized controlled trial publications

5,515

5,515 peptide publications report randomized controlled trials in humans.

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Human clinical vs. preclinical peptide research

Counted publications in the analysis window by evidence class.

Human clinical research: 24,249Reviews and meta-analyses: 10,563Animal studies: 17,799In vitro studies: 6,427Computational studies: 796Commentary and other: 4,245Not yet classified: 389Human clinical re…24,249Reviews and meta-…10,563Animal studies17,799In vitro studies6,427Computational stu…796Commentary and ot…4,245Not yet classified389

Every publication is in exactly one class, so the bars add up to the total. Publication counts do not measure evidence quality.

Source: Peptide Library Research Intelligence Center · Automated weekly refresh, data through November 1, 2026

Show the data
Human clinical vs. preclinical peptide research
ItemPublications
Human clinical research24,249
Reviews and meta-analyses10,563
Animal studies17,799
In vitro studies6,427
Computational studies796
Commentary and other4,245
Not yet classified389
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Human, animal and laboratory research by year

Counted publications by evidence class and year.

2000, Human clinical research: 548 of 1,6312000, Reviews and meta-analyses: 175 of 1,6312000, Animal studies: 653 of 1,6312000, In vitro studies: 180 of 1,6312000, Computational studies: 2 of 1,6312000, Commentary and other: 64 of 1,6312000, Not yet classified: 9 of 1,6312001, Human clinical research: 523 of 1,5892001, Reviews and meta-analyses: 200 of 1,5892001, Animal studies: 600 of 1,5892001, In vitro studies: 180 of 1,5892001, Computational studies: 5 of 1,5892001, Commentary and other: 65 of 1,5892001, Not yet classified: 16 of 1,5892002, Human clinical research: 570 of 1,6672002, Reviews and meta-analyses: 214 of 1,6672002, Animal studies: 617 of 1,6672002, In vitro studies: 159 of 1,6672002, Computational studies: 7 of 1,6672002, Commentary and other: 87 of 1,6672002, Not yet classified: 13 of 1,6672003, Human clinical research: 552 of 1,7062003, Reviews and meta-analyses: 246 of 1,7062003, Animal studies: 582 of 1,7062003, In vitro studies: 186 of 1,7062003, Computational studies: 7 of 1,7062003, Commentary and other: 120 of 1,7062003, Not yet classified: 13 of 1,7062004, Human clinical research: 663 of 1,7832004, Reviews and meta-analyses: 263 of 1,7832004, Animal studies: 546 of 1,7832004, In vitro studies: 208 of 1,7832004, Computational studies: 11 of 1,7832004, Commentary and other: 81 of 1,7832004, Not yet classified: 11 of 1,7832005, Human clinical research: 649 of 1,8302005, Reviews and meta-analyses: 267 of 1,8302005, Animal studies: 569 of 1,8302005, In vitro studies: 217 of 1,8302005, Computational studies: 14 of 1,8302005, Commentary and other: 103 of 1,8302005, Not yet classified: 11 of 1,8302006, Human clinical research: 633 of 1,8752006, Reviews and meta-analyses: 327 of 1,8752006, Animal studies: 573 of 1,8752006, In vitro studies: 219 of 1,8752006, Computational studies: 17 of 1,8752006, Commentary and other: 89 of 1,8752006, Not yet classified: 17 of 1,8752007, Human clinical research: 668 of 1,8332007, Reviews and meta-analyses: 320 of 1,8332007, Animal studies: 524 of 1,8332007, In vitro studies: 192 of 1,8332007, Computational studies: 16 of 1,8332007, Commentary and other: 101 of 1,8332007, Not yet classified: 12 of 1,8332008, Human clinical research: 665 of 1,8632008, Reviews and meta-analyses: 304 of 1,8632008, Animal studies: 537 of 1,8632008, In vitro studies: 227 of 1,8632008, Computational studies: 8 of 1,8632008, Commentary and other: 105 of 1,8632008, Not yet classified: 17 of 1,8632009, Human clinical research: 708 of 1,9372009, Reviews and meta-analyses: 309 of 1,9372009, Animal studies: 559 of 1,9372009, In vitro studies: 233 of 1,9372009, Computational studies: 18 of 1,9372009, Commentary and other: 100 of 1,9372009, Not yet classified: 10 of 1,9372010, Human clinical research: 750 of 2,0672010, Reviews and meta-analyses: 350 of 2,0672010, Animal studies: 595 of 2,0672010, In vitro studies: 228 of 2,0672010, Computational studies: 17 of 2,0672010, Commentary and other: 116 of 2,0672010, Not yet classified: 11 of 2,0672011, Human clinical research: 805 of 2,0732011, Reviews and meta-analyses: 331 of 2,0732011, Animal studies: 563 of 2,0732011, In vitro studies: 238 of 2,0732011, Computational studies: 17 of 2,0732011, Commentary and other: 112 of 2,0732011, Not yet classified: 7 of 2,0732012, Human clinical research: 837 of 2,2862012, Reviews and meta-analyses: 405 of 2,2862012, Animal studies: 624 of 2,2862012, In vitro studies: 254 of 2,2862012, Computational studies: 20 of 2,2862012, Commentary and other: 133 of 2,2862012, Not yet classified: 13 of 2,2862013, Human clinical research: 863 of 2,3282013, Reviews and meta-analyses: 375 of 2,3282013, Animal studies: 670 of 2,3282013, In vitro studies: 233 of 2,3282013, Computational studies: 20 of 2,3282013, Commentary and other: 160 of 2,3282013, Not yet classified: 7 of 2,3282014, Human clinical research: 846 of 2,3442014, Reviews and meta-analyses: 344 of 2,3442014, Animal studies: 730 of 2,3442014, In vitro studies: 251 of 2,3442014, Computational studies: 32 of 2,3442014, Commentary and other: 135 of 2,3442014, Not yet classified: 6 of 2,3442015, Human clinical research: 945 of 2,3972015, Reviews and meta-analyses: 318 of 2,3972015, Animal studies: 701 of 2,3972015, In vitro studies: 247 of 2,3972015, Computational studies: 21 of 2,3972015, Commentary and other: 156 of 2,3972015, Not yet classified: 9 of 2,3972016, Human clinical research: 925 of 2,4412016, Reviews and meta-analyses: 414 of 2,4412016, Animal studies: 676 of 2,4412016, In vitro studies: 261 of 2,4412016, Computational studies: 22 of 2,4412016, Commentary and other: 135 of 2,4412016, Not yet classified: 8 of 2,4412017, Human clinical research: 881 of 2,4412017, Reviews and meta-analyses: 374 of 2,4412017, Animal studies: 687 of 2,4412017, In vitro studies: 273 of 2,4412017, Computational studies: 36 of 2,4412017, Commentary and other: 182 of 2,4412017, Not yet classified: 8 of 2,4412018, Human clinical research: 891 of 2,4672018, Reviews and meta-analyses: 400 of 2,4672018, Animal studies: 759 of 2,4672018, In vitro studies: 265 of 2,4672018, Computational studies: 31 of 2,4672018, Commentary and other: 119 of 2,4672018, Not yet classified: 2 of 2,4672019, Human clinical research: 931 of 2,4792019, Reviews and meta-analyses: 336 of 2,4792019, Animal studies: 712 of 2,4792019, In vitro studies: 301 of 2,4792019, Computational studies: 37 of 2,4792019, Commentary and other: 159 of 2,4792019, Not yet classified: 3 of 2,4792020, Human clinical research: 996 of 2,6332020, Reviews and meta-analyses: 388 of 2,6332020, Animal studies: 760 of 2,6332020, In vitro studies: 292 of 2,6332020, Computational studies: 40 of 2,6332020, Commentary and other: 152 of 2,6332020, Not yet classified: 5 of 2,6332021, Human clinical research: 1,033 of 2,7122021, Reviews and meta-analyses: 443 of 2,7122021, Animal studies: 733 of 2,7122021, In vitro studies: 270 of 2,7122021, Computational studies: 52 of 2,7122021, Commentary and other: 165 of 2,7122021, Not yet classified: 16 of 2,7122022, Human clinical research: 1,003 of 2,6502022, Reviews and meta-analyses: 446 of 2,6502022, Animal studies: 695 of 2,6502022, In vitro studies: 298 of 2,6502022, Computational studies: 55 of 2,6502022, Commentary and other: 143 of 2,6502022, Not yet classified: 10 of 2,6502023, Human clinical research: 1,061 of 2,8382023, Reviews and meta-analyses: 529 of 2,8382023, Animal studies: 705 of 2,8382023, In vitro studies: 241 of 2,8382023, Computational studies: 69 of 2,8382023, Commentary and other: 208 of 2,8382023, Not yet classified: 25 of 2,8382024, Human clinical research: 1,437 of 3,4892024, Reviews and meta-analyses: 623 of 3,4892024, Animal studies: 728 of 3,4892024, In vitro studies: 260 of 3,4892024, Computational studies: 47 of 3,4892024, Commentary and other: 367 of 3,4892024, Not yet classified: 27 of 3,4892025, Human clinical research: 1,907 of 4,4962025, Reviews and meta-analyses: 804 of 4,4962025, Animal studies: 897 of 4,4962025, In vitro studies: 276 of 4,4962025, Computational studies: 80 of 4,4962025, Commentary and other: 484 of 4,4962025, Not yet classified: 48 of 4,4962026 (to date), Human clinical research: 1,959 of 4,6132026 (to date), Reviews and meta-analyses: 1,058 of 4,6132026 (to date), Animal studies: 804 of 4,6132026 (to date), In vitro studies: 238 of 4,6132026 (to date), Computational studies: 95 of 4,6132026 (to date), Commentary and other: 404 of 4,6132026 (to date), Not yet classified: 55 of 4,613Human clinical researchReviews and meta-analysesAnimal studiesIn vitro studiesComputational studiesCommentary and otherNot yet classified02,0004,0006,00020002006201220182026*

Each bar splits a year's publications by the kind of evidence. A larger bar is more publications, not stronger evidence. * 2026 runs to November 1, 2026.

Source: Peptide Library Research Intelligence Center · Automated weekly refresh, data through November 1, 2026

Show the data
Human, animal and laboratory research by year
YearHuman clinical researchReviews and meta-analysesAnimal studiesIn vitro studiesComputational studiesCommentary and otherNot yet classifiedTotal
200054817565318026491,631
2001523200600180565161,589
2002570214617159787131,667
20035522465821867120131,706
20046632635462081181111,783
200564926756921714103111,830
20066333275732191789171,875
200766832052419216101121,833
20086653045372278105171,863
200970830955923318100101,937
201075035059522817116112,067
20118053315632381711272,073
201283740562425420133132,286
20138633756702332016072,328
20148463447302513213562,344
20159453187012472115692,397
20169254146762612213582,441
20178813746872733618282,441
20188914007592653111922,467
20199313367123013715932,479
20209963887602924015252,633
20211,03344373327052165162,712
20221,00344669529855143102,650
20231,06152970524169208252,838
20241,43762372826047367273,489
20251,90780489727680484484,496
2026 (to date)1,9591,05880423895404554,613
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By peptide

Share of peptides with any human clinical publication

83.9%

83.9% of studied peptides have at least one human clinical publication.

135 of 161

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Share of peptides studied only preclinically

14.9%

14.9% of studied peptides have been studied only preclinically.

24 of 161

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Most researched peptides

Counted publications per peptide in the analysis window.

Octreotide, Human clinical research: 3,191Octreotide, Preclinical (animal, in vitro, computational): 1,225Octreotide, Reviews and meta-analyses: 819Octreotide, Other and not yet classified: 277Semaglutide, Human clinical research: 1,947Semaglutide, Preclinical (animal, in vitro, computational): 698Semaglutide, Reviews and meta-analyses: 1,411Semaglutide, Other and not yet classified: 879Liraglutide, Human clinical research: 1,739Liraglutide, Preclinical (animal, in vitro, computational): 1,440Liraglutide, Reviews and meta-analyses: 1,322Liraglutide, Other and not yet classified: 409Exenatide, Human clinical research: 1,042Exenatide, Preclinical (animal, in vitro, computational): 2,079Exenatide, Reviews and meta-analyses: 912Exenatide, Other and not yet classified: 289Teriparatide, Human clinical research: 1,250Teriparatide, Preclinical (animal, in vitro, computational): 875Teriparatide, Reviews and meta-analyses: 680Teriparatide, Other and not yet classified: 260Klotho, Human clinical research: 1,073Klotho, Preclinical (animal, in vitro, computational): 1,391Klotho, Reviews and meta-analyses: 437Klotho, Other and not yet classified: 159PACAP-38, Human clinical research: 159PACAP-38, Preclinical (animal, in vitro, computational): 2,196PACAP-38, Reviews and meta-analyses: 415PACAP-38, Other and not yet classified: 81Orexin-A, Human clinical research: 424Orexin-A, Preclinical (animal, in vitro, computational): 1,787Orexin-A, Reviews and meta-analyses: 448Orexin-A, Other and not yet classified: 59Vasoactive Intestinal Peptide (VIP), Human clinical research: 357Vasoactive Intestinal Peptide (VIP), Preclinical (animal, in vitro, computational): 1,884Vasoactive Intestinal Peptide (VIP), Reviews and meta-analyses: 220Vasoactive Intestinal Peptide (VIP), Other and not yet classified: 42Leuprolide, Human clinical research: 1,594Leuprolide, Preclinical (animal, in vitro, computational): 473Leuprolide, Reviews and meta-analyses: 230Leuprolide, Other and not yet classified: 145Desmopressin, Human clinical research: 1,340Desmopressin, Preclinical (animal, in vitro, computational): 420Desmopressin, Reviews and meta-analyses: 301Desmopressin, Other and not yet classified: 155Tirzepatide, Human clinical research: 875Tirzepatide, Preclinical (animal, in vitro, computational): 194Tirzepatide, Reviews and meta-analyses: 765Tirzepatide, Other and not yet classified: 365LL-37, Human clinical research: 373LL-37, Preclinical (animal, in vitro, computational): 1,586LL-37, Reviews and meta-analyses: 157LL-37, Other and not yet classified: 51Bivalirudin, Human clinical research: 855Bivalirudin, Preclinical (animal, in vitro, computational): 131Bivalirudin, Reviews and meta-analyses: 379Bivalirudin, Other and not yet classified: 248Goserelin, Human clinical research: 844Goserelin, Preclinical (animal, in vitro, computational): 108Goserelin, Reviews and meta-analyses: 139Goserelin, Other and not yet classified: 86Human clinical researchPreclinical (animal, in vitro, computational)Reviews and meta-analysesOther and not yet classifiedOctreotide5,512Semaglutide4,935Liraglutide4,910Exenatide4,322Teriparatide3,065Klotho3,060PACAP-382,851Orexin-A2,718Vasoactive Intest…2,503Leuprolide2,442Desmopressin2,216Tirzepatide2,199LL-372,167Bivalirudin1,613Goserelin1,177

Longer bars mean more publications. Research volume says nothing about whether a peptide works or is safe.

Source: Peptide Library Research Intelligence Center · Automated weekly refresh, data through November 1, 2026

Show the data
Most researched peptides
ItemHuman clinical researchPreclinical (animal, in vitro, computational)Reviews and meta-analysesOther and not yet classifiedTotal
Octreotide3,1911,2258192775,512
Semaglutide1,9476981,4118794,935
Liraglutide1,7391,4401,3224094,910
Exenatide1,0422,0799122894,322
Teriparatide1,2508756802603,065
Klotho1,0731,3914371593,060
PACAP-381592,196415812,851
Orexin-A4241,787448592,718
Vasoactive Intestinal Peptide (VIP)3571,884220422,503
Leuprolide1,5944732301452,442
Desmopressin1,3404203011552,216
Tirzepatide8751947653652,199
LL-373731,586157512,167
Bivalirudin8551313792481,613
Goserelin844108139861,177
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Most researched peptides
#PeptidePublicationsHuman clinicalPreclinicalTrials
1Octreotide5,5123,1911,225253
2Semaglutide4,9351,947698649
3Liraglutide4,9101,7391,440456
4Exenatide4,3221,0422,079317
5Teriparatide3,0651,250875162
6Klotho3,0601,0731,3915
7PACAP-382,8511592,19613
8Orexin-A2,7184241,7870
9Vasoactive Intestinal Peptide (VIP)2,5033571,88415
10Leuprolide2,4421,594473380
11Desmopressin2,2161,340420103
12Tirzepatide2,199875194252
13LL-372,1673731,5865
14Bivalirudin1,61385513169
15Goserelin1,177844108301

Indexed peptides ranked by counted publications in the window. A publication counts once for each peptide it covers. Volume says nothing about effectiveness or safety. Definition

Most researched research-only peptides
#PeptidePublicationsHuman clinicalPreclinicalTrials
1Cerebrolysin50519019340
2GHRP-6290502330
3Melanotan II249321971
4BPC-15720141413
5Semax168131460
6Hexarelin (Examorelin)167261200
7Epitalon165171280
8Cortexin15387440
9Thymopentin150201189
10Pralmorelin (GHRP-2)14870680
11Sermorelin14161240
12GHK-Cu (Copper Peptide)1197941
13Angiotensin (1-7) Analog900810
14Selank665570
15Vilon584510

The same ranking for peptides with no FDA approval and no trial-stage label in the library, leaving out molecules the body makes itself. Definition

Research gaps

Peptides with at least 20 publications and the lowest share of human clinical research.

Completed trials without published results

33.2%

33.2% of completed peptide trials have no posted or linked results a year after completion.

911 of 2,743

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Peptides with the least human evidence
#PeptideHuman clinical sharePublicationsHuman clinical
1Angiotensin (1-7) Analog0.0%900
2KPV0.0%640
3IGF-1 DES0.0%270
4IGF-1 LR30.0%260
5Livagen0.0%200
6BPC-1571.8%2284
7Humanin-G (HNG)2.6%411
8PNC-274.3%231
9PACAP-384.5%3,895174
10Tuftsin4.8%62327
11TB-500 (Thymosin Beta-4 fragment)4.8%211
12GHK-Cu (Copper Peptide)5.6%1438
13Ipamorelin6.5%463
14Vilon6.8%594
15Elamipretide (SS-31)7.5%40930

Indexed peptides with at least the minimum number of counted publications, ranked by the lowest share of human clinical publications (all years to the cutoff). Definition

Data quality

Share not yet classified

0.6%

0.6% of peptide publications could not yet be classified by study type.

389 of 64,887

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Share classified with AI assistance

26.8%

26.8% of peptide publications were classified by study type with AI assistance, because their PubMed metadata could not decide it.

17,363 of 64,887

Definition

Data through November 1, 2026, version weekly-2026-11-01.

Retracted publications excluded

97

97 retracted publications were excluded.

Definition

Data through November 1, 2026, version weekly-2026-11-01.

What each evidence class means

Peptide Library sorts every counted PubMed publication into exactly one evidence class, from its PubMed publication type and MeSH terms; where those can't decide, an AI model reads the record and answers with a confidence score, and low-confidence answers are checked again or left unclassified. A MeSH tag "Humans" alone never makes a paper clinical. Registered trials come from ClinicalTrials.gov and are counted separately from publications.

Human clinical research
Randomized and other clinical trials, observational studies and case reports in people.
Reviews and meta-analyses
Reviews, systematic reviews and meta-analyses. They summarize other studies and report no new primary data.
Animal studies
Experiments in living animals, including veterinary trials.
In vitro studies
Cells, tissues or biochemical assays outside a living organism, human cells included.
Computational studies
Modelling, docking and simulation with no new laboratory or clinical data.
Commentary and other
Editorials, letters, comments, guidelines and similar.
Not yet classified
The PubMed metadata could not decide the study type and no confident AI answer exists yet.