Avidity Partners Management LP David Witzke

Dallas, TX 21 processed 13Fs on this site, 2021 Q3 to 2026 Q2

$624M
45 holdings
2026 Q2
+41.2% QoQ
Top 5 70.9%

Portfolio

2026 Q2, filed 8/14/2026, top 12 of 45 holdings

Top 5 70.9%, top 10 81.9%

AUM over time

2026 Q2 $624M +41.2% QoQ

Q3 2021

Q1 2022

Q1 2023

Q1 2024

Q1 2025

Q1 2026

Book

2023 Q2 2023 Q1, filed 14 Aug, long equity only

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BDX, Becton Dickinson	3.67%, was 2.37%	Add +38.2%	398,050	$264.01	$105M	+110,050	+$34M
Karuna Therapeutics	3.35%, was 2.43%	Add +9.5%	442,200	$216.85	$96M	+38,400	+$23M
JAZZ, Jazz Pharmaceuticals	3.04%	Add +3.7%	702,778	$123.97	$87M	+24,878	−$12M
GEHC, GE HealthCare	2.97%	New	1,045,400	$81.24	$85M	+1,045,400	+$85M
THC, Tenet Healthcare	2.82%, was 2.90%	Reduce −32.7%	990,500	$81.38	$81M	−481,500	−$6.9M
ARGX, Argenx	2.51%, was 3.47%	Reduce −34.3%	184,300	$389.73	$72M	−96,400	−$33M
IDYA, Ideaya Biosciences	2.45%	Reduce −18.7%	2,985,700	$23.50	$70M	−687,700	+$20M
SGRY, Surgery Partners	2.44%, was 3.84%	Reduce −53.7%	1,555,000	$44.99	$70M	−1,800,900	−$46M
ABBV, AbbVie	2.44%	New	518,400	$134.73	$70M	+518,400	+$70M
ARVN, Arvinas	2.40%, was 3.88%	Reduce −35.1%	2,773,189	$24.82	$69M	−1,500,711	−$48M
ZNTL, Zentalis Pharmaceuticals	2.30%	Reduce −20.3%	2,334,000	$28.21	$66M	−595,300	+$15M
NBIX, Neurocrine Biosciences	2.19%, was 2.74%	Reduce −18.4%	665,316	$94.30	$63M	−150,384	−$20M
LLY, Eli Lilly	2.18%	New	133,000	$468.98	$62M	+133,000	+$62M
SNDX, Syndax Pharmaceuticals	2.10%, was 2.71%	Reduce −25.7%	2,872,000	$20.93	$60M	−993,300	−$22M
UHS, Universal Health Services	2.04%, was 2.83%	Reduce −44.8%	370,100	$157.77	$58M	−299,900	−$27M
BIO, Bio Rad Labs	2.02%, was 3.52%	Reduce −31.1%	152,600	$379.12	$58M	−68,900	−$48M
COR, Amerisourcebergen	2.02%, was 0.67%	Add +137.0%	300,000	$192.43	$58M	+173,400	+$37M
PACB	2.01%, was 1.47%	Add +13.8%	4,337,400	$13.30	$58M	+524,800	+$14M
Legend Biotech	1.93%	Reduce −28.7%	798,900	$69.03	$55M	−321,600	+$1.1M
BIIB, Biogen	1.73%, was 1.19%	Add +35.1%	174,000	$284.85	$50M	+45,200	+$14M
Akero Therapeutics	1.67%, was 3.11%	Reduce −58.1%	1,025,000	$46.69	$48M	−1,422,000	−$46M
Curevac	1.56%, was 0.82%	Add +21.1%	4,300,000	$10.42	$45M	+750,000	+$20M
ACHC	1.53%, was 2.79%	Reduce −52.8%	550,000	$79.64	$44M	−615,300	−$40M
PCVX, Vaxcyte	1.53%, was 0.63%	Add +71.6%	875,000	$49.94	$44M	+365,000	+$25M
MCK, McKesson	1.51%	New	101,200	$427.31	$43M	+101,200	+$43M
APLS, Apellis Pharmaceuticals	1.49%	New	468,700	$91.10	$43M	+468,700	+$43M
BSX, Boston Scientific	1.48%	Reduce −7.6%	785,700	$54.09	$42M	−64,300	−$27K
RARE	1.45%, was 2.83%	Reduce −57.7%	900,700	$46.13	$42M	−1,226,200	−$44M
PFE, Pfizer	1.43%	New	1,117,467	$36.68	$41M	+1,117,467	+$41M
IMVT, Immunovant	1.38%, was 0.54%	Add +99.9%	2,085,000	$18.97	$40M	+1,042,000	+$23M
AXSM, Axsome Therapeutics	1.37%	Reduce −12.0%	545,000	$71.86	$39M	−74,200	+$971K
Immunogen	1.32%	New	1,997,800	$18.87	$38M	+1,997,800	+$38M
ZTS, Zoetis	1.31%, was 2.25%	Reduce −46.7%	217,000	$172.21	$37M	−190,500	−$30M
PRTA, Prothena	1.28%, was 1.72%	Reduce −49.9%	535,000	$68.28	$37M	−533,200	−$15M
VIR, Vir Biotechnology	1.22%, was 1.27%	Reduce −13.1%	1,425,000	$24.53	$35M	−215,200	−$3.2M
Immunocore	1.20%, was 1.26%	Reduce −25.3%	575,000	$59.96	$34M	−194,800	−$3.6M
Sarepta Therapeutics	1.19%, was 1.90%	Reduce −28.5%	297,500	$114.52	$34M	−118,500	−$23M
ARWR, Arrowhead Pharmaceuticals	1.15%, was 1.47%	Reduce −46.9%	925,000	$35.66	$33M	−816,300	−$11M
BHVN, Biohaven	1.11%	Reduce −10.9%	1,325,000	$23.92	$32M	−162,200	+$11M
RVMD, Revolution Medicines	1.00%	Reduce −20.1%	1,075,000	$26.75	$29M	−269,800	−$372K
PRVA, Privia Health Group	0.98%	New	1,079,806	$26.11	$28M	+1,079,806	+$28M
PHAT, Phathom Pharmaceuticals	0.98%	Reduce −4.8%	1,949,700	$14.32	$28M	−98,900	+$13M
BAX, Baxter International	0.96%	New	604,700	$45.56	$28M	+604,700	+$28M
Fusion Pharmaceuticals	0.93%	Hold	5,700,000	$4.67	$27M	—	—
RCKT, Rocket Pharmaceuticals	0.92%, was 0.71%	Add +6.6%	1,326,000	$19.87	$26M	+81,600	+$5M
Blueprint Medicines	0.92%	New	415,000	$63.20	$26M	+415,000	+$26M
EDIT, Editas Medicine	0.86%	New	3,000,000	$8.23	$25M	+3,000,000	+$25M
Ventyx Biosciences	0.79%, was 2.13%	Reduce −63.9%	692,500	$32.80	$23M	−1,225,300	−$42M
NTRA, Natera	0.74%, was 0.46%	Add +73.2%	432,900	$48.66	$21M	+183,000	+$7.2M
LNTH, Lantheus	0.72%	New	245,100	$83.92	$21M	+245,100	+$21M
MLTX, Moonlake Immunotherapeutics	0.71%	New	400,000	$51.00	$20M	+400,000	+$20M
Holding	0.70%, was 0.59%	Add +8.6%	954,500	$21.14	$20M	+75,700	+$2.5M
AMLX, Amylyx Pharmaceuticals	0.68%	Add +0.2%	901,400	$21.57	$19M	+1,400	−$7M
Axonics	0.67%	New	379,700	$50.47	$19M	+379,700	+$19M
XENE, Xenon Pharmaceuticals	0.65%	New	481,300	$38.50	$19M	+481,300	+$19M
REGN, Regeneron	0.62%, was 3.25%	Reduce −79.2%	24,800	$718.54	$18M	−94,300	−$80M
ROIV, Roivant Sciences	0.59%	New	1,687,500	$10.08	$17M	+1,687,500	+$17M
PLRX, Pliant Therapeutics	0.58%, was 2.35%	Reduce −65.6%	916,600	$18.12	$17M	−1,748,400	−$54M
Verve Therapeutics	0.58%, was 0.65%	Reduce −35.0%	878,600	$18.75	$16M	−473,100	−$3M
INTC, Intellia Therapeutics	0.56%	Reduce −5.1%	395,855	$40.78	$16M	−21,145	+$601K
Holding	0.56%	New	501,200	$31.79	$16M	+501,200	+$16M
Acelyrin	0.55%	New	750,000	$20.90	$16M	+750,000	+$16M
Point Biopharma Global	0.53%, was 0.58%	Reduce −30.7%	1,671,800	$9.06	$15M	−739,800	−$2.4M
Karyopharm Therapeutics	0.52%, was 1.24%	Reduce −13.1%	8,370,100	$1.79	$15M	−1,263,811	−$22M
Kezar Life Sciences	0.52%, was 0.68%	Reduce −6.7%	6,080,000	$2.45	$15M	−439,400	−$5.5M
SDGR, Schrodinger	0.48%	New	274,900	$49.92	$14M	+274,900	+$14M
2seventy Bio	0.47%	New	1,342,000	$10.12	$14M	+1,342,000	+$14M
MLYS, Mineralys Therapeutics	0.46%, was 0.66%	Reduce −39.3%	766,700	$17.05	$13M	−497,100	−$6.7M
Mersana Therapeutics	0.44%	Add +10.4%	3,790,000	$3.29	$12M	+356,767	−$1.6M
CRBU, Caribou Biosciences	0.41%	Hold	2,758,600	$4.25	$12M	—	—
Nanostring Technologies	0.38%	Add +21.8%	2,700,400	$4.05	$11M	+483,400	−$11M
Alpine Immune Sciences	0.38%, was 0.25%	Add +7.0%	1,058,500	$10.28	$11M	+69,000	+$3.2M
Inari Medical	0.36%	New	175,000	$58.14	$10M	+175,000	+$10M
89bio	0.35%, was 0.93%	Reduce −71.4%	526,376	$18.95	$10M	−1,316,600	−$18M
Ac Immune	0.30%, was 0.03%	Add +792.2%	2,903,278	$2.96	$8.6M	+2,577,878	+$7.8M
DNLI, Denali Therapeutics	0.29%	New	282,752	$29.51	$8.3M	+282,752	+$8.3M
COLL, Collegium Pharmaceutical	0.27%, was 0.31%	Reduce −8.1%	354,100	$21.49	$7.6M	−31,400	−$1.6M
ATEC, Alphatec	0.25%	New	393,000	$17.98	$7.1M	+393,000	+$7.1M
ANTX, An2 Therapeutics	0.20%, was 0.24%	Reduce −9.1%	657,200	$8.50	$5.6M	−66,000	−$1.6M
Gritstone Bio	0.19%	New	2,765,500	$1.95	$5.4M	+2,765,500	+$5.4M
CMPX, Compass Therapeutics	0.18%, was 0.20%	Reduce −11.2%	1,620,200	$3.18	$5.2M	−204,800	−$816K
SCYX, Scynexis	0.18%	New	1,738,734	$2.95	$5.1M	+1,738,734	+$5.1M
Syros Pharmaceuticals	0.16%, was 0.08%	Add +61.8%	1,464,034	$3.15	$4.6M	+559,404	+$2.2M
ALT, Altimmune	0.14%, was 0.18%	Reduce −10.7%	1,174,100	$3.53	$4.1M	−141,100	−$1.4M
IPSC, Century Therapeutics	0.12%, was 0.15%	Reduce −12.4%	1,110,900	$3.16	$3.5M	−157,200	−$890K
Hyperfine	0.09%	Reduce −21.0%	1,188,178	$2.15	$2.6M	−315,576	+$389K
SLP, Simulations Plus	0.07%	New	45,900	$43.33	$2M	+45,900	+$2M
Caremax	0.07%	Reduce −15.8%	636,000	$3.11	$2M	−119,329	−$39K
BHC, Bausch Health Companies	0.06%	New	215,100	$8.00	$1.7M	+215,100	+$1.7M
GPCR, Structure Therapeutics	0.05%	New	37,800	$41.57	$1.6M	+37,800	+$1.6M
Exscientia	0.03%	New	127,600	$5.92	$755K	+127,600	+$755K
AIP, Arteris	0.02%	New	75,500	$6.82	$515K	+75,500	+$515K

Showing top 50 of 92 by value

Exits / last held

Gone since 2023 Q1, shown at their last reported size.

Stock	% of portfolio	Recent activity	Reported price*	Value	Share change	$ change
MRK, Merck	2.12%	Exit	$106.39	$64M	−600,000	−$64M
Iveric Bio	1.51%	Exit	$24.33	$45M	−1,869,200	−$45M
ABT, Abbott Laboratories	1.19%	Exit	$101.26	$36M	−354,000	−$36M
Bellus Health	1.09%	Exit	$7.20	$33M	−4,553,577	−$33M
ICLR, Icon	1.01%	Exit	$213.59	$31M	−142,900	−$31M
BMRN, Biomarin Pharmaceutical	0.97%	Exit	$97.24	$29M	−300,575	−$29M
AVTR, Avantor	0.79%	Exit	$21.14	$24M	−1,125,000	−$24M
RNA, Avidity Biosciences	0.64%	Exit	$15.35	$19M	−1,265,545	−$19M
ARQT, Arcutis Biotherapeutics	0.59%	Exit	$11.00	$18M	−1,628,500	−$18M
DXCM, DexCom	0.57%	Exit	$116.18	$17M	−148,000	−$17M
BBIO, Bridgebio	0.55%	Exit	$16.58	$17M	−1,000,000	−$17M
TWST, Twist Bioscience	0.41%	Exit	$15.08	$12M	−819,000	−$12M
CYTK, Cytokinetics	0.29%	Exit	$35.19	$8.9M	−252,000	−$8.9M
Kinnate Biopharma	0.24%	Exit	$6.25	$7.3M	−1,160,000	−$7.3M
GERN, Geron	0.15%	Exit	$2.17	$4.6M	−2,128,000	−$4.6M
Sangamo Therapeutics	0.14%	Exit	$1.76	$4.3M	−2,470,000	−$4.3M
Holding	0.11%	Exit	$0.8090	$3.5M	−4,281,700	−$3.5M
Cyteir Therapeutics	0.11%	Exit	$1.82	$3.2M	−1,764,100	−$3.2M
BCAB, Bioatla	0.05%	Exit	$2.68	$1.6M	−602,500	−$1.6M
Reunion Neuroscience	—	Exit	$0.6883	$104K	−151,098	−$104K

Filings history

20 periods, with AUM normalized

Newest 13Fs

Period	Holds	AUM	QoQ	Form	Filed	Filing ID
2026 Q2	45	$624M	+41.2%	13F-HR	8/14/2026	000179182726000005
2026 Q1	45	$494M	—	new holds	5/28/2026	000179182726000004
2026 Q1	46	$442M	+27.4%	13F-HR	5/13/2026	000179182726000003
2025 Q4	39	$347M	−21.0%	13F-HR	2/13/2026	000179182726000002
2025 Q3	43	$439M	−12.5%	13F-HR	11/14/2025	000179182725000008
2025 Q2	56	$502M	−4.4%	13F-HR	8/14/2025	000179182725000007
2025 Q1	67	$525M	−48.4%	13F-HR	5/15/2025	000179182725000005
2024 Q4	63	$1B	−48.1%	13F-HR	2/14/2025	000179182725000002
2024 Q3	81	$2B	−16.7%	13F-HR	11/14/2024	000179182724000011
2024 Q2	85	$2.4B	−24.1%	13F-HR	8/14/2024	000179182724000007
2024 Q1	90	$3.1B	+13.0%	13F-HR	5/15/2024	000179182724000004
2023 Q4	74	$2.7B	+10.5%	13F-HR	2/14/2024	000179182724000002
2023 Q3	83	$2.5B	−13.3%	13F-HR	11/14/2023	000179182723000006
2023 Q2	93	$2.9B	−5.0%	13F-HR	8/14/2023	000179182723000004
2023 Q1	83	$3B	−34.7%	13F-HR	5/15/2023	000179182723000003
2022 Q4	85	$4.6B	−6.2%	13F-HR	2/14/2023	000179182723000002
2022 Q3	97	$4.9B	+12.9%	13F-HR	11/14/2022	000179182722000008
2022 Q2	82	$4.4B	−9.3%	13F-HR	8/15/2022	000179182722000006
2022 Q1	92	$4.8B	+1.9%	13F-HR	5/16/2022	000179182722000004
2021 Q4	97	$4.7B	+4.5%	13F-HR	2/14/2022	000179182722000002
2021 Q3	105	$4.5B	—	13F-HR	11/15/2021	000179182721000006

About

Avidity Partners Management LP

21 processed 13Fs on this site, 2021 Q3 to 2026 Q2

Entity: Avidity Partners Management LP
Notable person: David Witzke
Location: Dallas, TX
All SEC filings: View on sec.gov

Filings history

Avidity Partners Management LP

Further reading