Latest Palo Alto Investors LP Stock Portfolio

$653Million– No. of Holdings #51

Palo Alto Investors LP Performance:

2026 Q1: -2.1%YTD: -2.1%2025: 31.91%

Performance for 2026 Q1 is -2.1%, and YTD is -2.1%, and 2025 is 31.91%.

About Palo Alto Investors LP and 13F Hedge Fund Stock Holdings

Palo Alto Investors LP is a hedge fund based in Palo Alto, CA. On 2026-05-15, the fund reported it's updated stock portfolio. In the 13F Holdings report, Palo Alto Investors LP reported an equity portfolio of $653.9 Millions as of 31 Mar, 2026.

The top stock holdings of Palo Alto Investors LP are INSM, ACAD, PTCT. The fund has invested 10.4% of it's portfolio in INSMED INC and 9.8% of portfolio in ACADIA PHARMACEUTICALS INC.

The fund managers got completely rid off GOSSAMER BIO INC (GOSS), GENERATION BIO CO (GBIO) and AKARI THERAPEUTICS PLC-ADR (AKTX) stocks. They significantly reduced their stock positions in AMICUS THERAPEUTICS INC (FOLD), DENALI THERAPEUTICS INC (DNLI) and XENON PHARMACEUTICALS INC (XENE). Palo Alto Investors LP opened new stock positions in CELLDEX THERAPEUTICS INC (CLDX), CYTOKINETICS INC (CYTK) and VERASTEM INC (VSTM). The fund showed a lot of confidence in some stocks as they added substantially to TRAVERE THERAPEUTICS INC (TVTX), MIRUM PHARMACEUTICALS INC (MIRM) and BICARA THERAPEUTICS INC.

Palo Alto Investors LP Equity Portfolio Value

Last Reported on: 15 May, 2026

Palo Alto Investors LP Annual Return Estimates Vs S&P 500

Our best estimate is that Palo Alto Investors LP made a return of -2.1% in the last quarter. In trailing 12 months, it's portfolio return was 40.34%.

Performance
S&P 500

New Buys

Ticker	$ Bought
celldex therapeutics inc	9,402,060
cytokinetics inc	2,121,970
verastem inc	1,304,290
madrigal pharmaceuticals inc	935,441
xeris biopharma holdings inc	605,578

New stocks bought by Palo Alto Investors LP

Additions

Ticker	% Inc.
travere therapeutics inc	108
mirum pharmaceuticals inc	107
bicara therapeutics inc	84.34
ultragenyx pharmaceutical in	29.31
disc medicine inc	26.54
annexon inc	23.65
taysha gene therapies inc	17.6
stoke therapeutics inc	17.51

Additions to existing portfolio by Palo Alto Investors LP

Reductions

Ticker	% Reduced
amicus therapeutics inc	-78.62
denali therapeutics inc	-63.42
xenon pharmaceuticals inc	-46.8
compass therapeutics inc	-40.2
aldeyra therapeutics inc	-30.94
biogen inc	-23.34
insmed inc	-15.16
iovance biotherapeutics inc	-10.78

Palo Alto Investors LP reduced stake in above stock

Sold off

Ticker	$ Sold
gossamer bio inc	-13,861,900
akari therapeutics plc-adr	-42,201
generation bio co	-85,467

Palo Alto Investors LP got rid off the above stocks

Sector Distribution

Palo Alto Investors LP has about 93.3% of it's holdings in Healthcare sector.

Healthcare
Others

Sector	%
Healthcare	93.3
Others	6.4

Market Cap. Distribution

Palo Alto Investors LP has about 28.1% of it's portfolio invested in the large-cap and mega-cap stocks.

MID-CAP
SMALL-CAP
LARGE-CAP
UNALLOCATED

Category	%
MID-CAP	35.1
SMALL-CAP	29.8
LARGE-CAP	28.1
UNALLOCATED	6.4

Stocks belong to which Index?

About 74.1% of the stocks held by Palo Alto Investors LP either belong to S&P 500 or RUSSELL 2000 index.

RUSSELL 2000
Others
S&P 500

Index	%
RUSSELL 2000	68.5
Others	26
S&P 500	5.6

Top 5 Winners (%)		%
	oruka therapeutics inc	61.8 %
IOVA	iovance biotherapeutics inc	27.0 %
PYXS	pyxis oncology inc	26.6 %
ALKS	alkermes plc	26.4 %
AGIO	agios pharmaceuticals inc	24.2 %

Top 5 Winners ($)		$
UTHR	united therapeutics corp	6.4 M
IOVA	iovance biotherapeutics inc	5.3 M
ANAB	anaptysbio inc	4.6 M
MIRM	mirum pharmaceuticals inc	3.2 M
SNDX	syndax pharmaceuticals inc	1.9 M

Top 5 Losers (%)		%
EHTH	ehealth inc	-70.8 %
ALDX	aldeyra therapeutics inc	-57.0 %
NUVB	nuvation bio inc	-50.7 %
INSP	inspire medical systems inc	-44.1 %
BCYC	bicycle therapeutics plc-adr	-33.0 %

Top 5 Losers ($)		$
ACAD	acadia pharmaceuticals inc	-11.9 M
PTCT	ptc therapeutics inc	-7.1 M
	disc medicine inc	-5.6 M
EHTH	ehealth inc	-5.0 M
INSM	insmed inc	-4.8 M

Palo Alto Investors LP Holdings Map

This heatmap illustrates the top 50 positions within the fund's portfolio.

Current Stock Holdings of Palo Alto Investors LP

Palo Alto Investors LP has 51 stocks in it's portfolio. About 63.8% of the portfolio is in top 10 stocks. ACAD proved to be the most loss making stock for the portfolio. UTHR was the most profitable stock for Palo Alto Investors LP last quarter.

Last Reported on: 15 May, 2026

Ticker	Namesorted ascending	% Portfolio	Shares Held	$ Value	Type	% Change
ABEO	abeona therapeutics inc	0.07	108,865	487,715	unchanged	0.00

ACAD	acadia pharmaceuticals inc	9.78	2,872,700	63,946,200	added	15.65

ACRS	aclaris therapeutics inc	0.92	1,613,430	6,050,360	added	2.97

AGIO	agios pharmaceuticals inc	1.10	213,601	7,226,120	added	0.52

AKTX	akari therapeutics plc-adr	0.00	0.00	0.00	sold off	-100

ALDX	aldeyra therapeutics inc	0.04	155,709	263,148	reduced	-30.94

ALGN	align technology inc	1.09	41,520	7,117,770	unchanged	0.00

ALKS	alkermes plc	1.31	242,560	8,576,920	unchanged	0.00

ANAB	anaptysbio inc	5.41	957,237	35,392,400	reduced	-7.52

ANNX	annexon inc	2.50	2,948,090	16,332,400	added	23.65

BCYC	bicycle therapeutics plc-adr	0.14	201,890	936,770	reduced	-8.68

BIIB	biogen inc	3.94	140,719	25,798,000	reduced	-23.34

BMRN	biomarin pharmaceutical inc	5.92	685,182	38,705,900	reduced	-8.18

BNTX	biontech se-adr	0.27	19,614	1,743,290	unchanged	0.00

CAPR	capricor therapeutics inc	1.07	229,763	6,984,800	added	1.53

CDNA	caredx inc	1.41	531,870	9,233,260	added	11.22

CLDX	celldex therapeutics inc	1.44	296,408	9,402,060	new

CMPS	compass pathways plc adr	0.10	115,616	639,356	unchanged	0.00

CMPX	compass therapeutics inc	1.23	1,514,500	8,011,730	reduced	-40.2

CRSP	crispr therapeutics ag	0.29	39,605	1,884,010	reduced	-3.93