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Ionis Pharmaceuticals (IONS)


Market Price (12/18/2025): $77.12 | Market Cap: $12.3 Bil
Sector: Health Care | Industry: Biotechnology

Ionis Pharmaceuticals (IONS)


Market Price (12/18/2025): $77.12
Market Cap: $12.3 Bil
Sector: Health Care
Industry: Biotechnology

Investment Highlights Why It Matters Which of these 2 stories sounds closer for this stock?

1. Generates cash flow

The stock generated 4% or more of the share price (called cash flow yield), and shows moderate 10-15% or more growth.

2. Riding a trend

Think Tesla during the pandemic of 2020 when EVs were riding a cultural high, or Nvidia in the current AI boom, or even Figma. These companies don’t have enough yield, or, enough growth, or both - however - they are riding a trend. They have momentum. These can be more volatile - they don’t have the floor of strong cash flow


0 Megatrend and thematic drivers
Megatrends include Biotechnology & Genomics, and Precision Medicine. Themes include Gene Editing & Therapy, Targeted Therapies, Show more.
Not profitable at operating income level
Op Inc LTMOperating Income, Last Twelve Months is -278 Mil, Op Mgn LTMOperating Margin = Operating Income / Revenue Reflects profitability before taxes and before impact of capital structure (interest payments). is -29%
1  Stock price has recently run up significantly
6M Rtn6 month market price return is 108%, 12M Rtn12 month market price return is 105%
2  Not cash flow generative
CFO/Rev LTMCash Flow from Operations / Revenue (Sales), Last Twelve Months (LTM) is -26%, FCF/Rev LTMFree Cash Flow / Revenue (Sales), Last Twelve Months (LTM) is -32%
3  Valuation getting more expensive
P/S 6M Chg %Price/Sales change over 6 months. Declining P/S indicates valuation has become less expensive. is 62%
4  Yield minus risk free rate is negative
ERPEquity Risk Premium (ERP) = Total Yield - Risk Free Rate, Reflects the premium above risk free assets offered by the investment. is -6.6%
5  Key risks
IONS key risks include [1] ongoing patent infringement lawsuits with Arrowhead Pharmaceuticals and [2] challenges in its strategic transition to independently commercializing its own products.
0 Megatrend and thematic drivers
Megatrends include Biotechnology & Genomics, and Precision Medicine. Themes include Gene Editing & Therapy, Targeted Therapies, Show more.
1 Not profitable at operating income level
Op Inc LTMOperating Income, Last Twelve Months is -278 Mil, Op Mgn LTMOperating Margin = Operating Income / Revenue Reflects profitability before taxes and before impact of capital structure (interest payments). is -29%
2 Stock price has recently run up significantly
6M Rtn6 month market price return is 108%, 12M Rtn12 month market price return is 105%
3 Not cash flow generative
CFO/Rev LTMCash Flow from Operations / Revenue (Sales), Last Twelve Months (LTM) is -26%, FCF/Rev LTMFree Cash Flow / Revenue (Sales), Last Twelve Months (LTM) is -32%
4 Valuation getting more expensive
P/S 6M Chg %Price/Sales change over 6 months. Declining P/S indicates valuation has become less expensive. is 62%
5 Yield minus risk free rate is negative
ERPEquity Risk Premium (ERP) = Total Yield - Risk Free Rate, Reflects the premium above risk free assets offered by the investment. is -6.6%
6 Key risks
IONS key risks include [1] ongoing patent infringement lawsuits with Arrowhead Pharmaceuticals and [2] challenges in its strategic transition to independently commercializing its own products.

Valuation, Metrics & Events

IONS Stock


Why The Stock Moved


Qualitative Assessment

AI Generated Analysis | Feedback

Here are the key points explaining the stock movement for Ionis Pharmaceuticals (IONS) from approximately August 31, 2025, to today:

1. FDA Approval of DAWNZERA for Hereditary Angioedema: Ionis Pharmaceuticals received U.S. FDA approval for DAWNZERA (donidalorsen) on August 21, 2025, as the first and only RNA-targeted prophylactic treatment for hereditary angioedema (HAE). This marked a significant milestone as the company's second independent product launch within a year, indicating its growing commercial capabilities and addressing an unmet medical need.

2. Positive Phase 3 Results for Olezarsen in Severe Hypertriglyceridemia (sHTG): On September 2, 2025, and further elaborated on October 23, 2025, Ionis announced that olezarsen demonstrated highly statistically significant reductions in fasting triglycerides (up to 72%) and acute pancreatitis events (85%) in the landmark pivotal CORE and CORE2 studies for severe hypertriglyceridemia. These positive results positioned olezarsen for a supplementary new drug application (sNDA) submission by year-end, targeting a much larger patient population.

Show more

Stock Movement Drivers

Return vs. Risk


Price Returns Compared

 202020212022202320242025Total [1]
Returns
IONS Return-6%-46%24%34%-31%124%30%
Peers Return11%-8%18%-7%-6%51%59%
S&P 500 Return16%27%-19%24%23%14%108%

Monthly Win Rates [3]
IONS Win Rate42%33%58%58%25%67% 
Peers Win Rate53%48%58%43%40%60% 
S&P 500 Win Rate58%75%42%67%75%73% 

Max Drawdowns [4]
IONS Max Drawdown-31%-55%-2%-11%-33%-27% 
Peers Max Drawdown-30%-24%-28%-31%-23%-35% 
S&P 500 Max Drawdown-31%-1%-25%-1%-2%-15% 


[1] Cumulative total returns since the beginning of 2020
[2] Peers: ALNY, BIIB, VRTX, SRPT, ARWR. See IONS Returns vs. Peers.
[3] Win Rate = % of calendar months in which monthly returns were positive
[4] Max drawdown represents maximum peak-to-trough decline within a year
[5] 2025 data is for the year up to 12/17/2025 (YTD)

How Low Can It Go

Unique KeyEventIONSS&P 500
2022 Inflation Shock2022 Inflation Shock  
2022 Inflation Shock% Loss% Loss-59.8%-25.4%
2022 Inflation Shock% Gain to Breakeven% Gain to Breakeven149.0%34.1%
2022 Inflation ShockTime to BreakevenTime to Breakeven1,378 days464 days
2020 Covid Pandemic2020 Covid Pandemic  
2020 Covid Pandemic% Loss% Loss-34.4%-33.9%
2020 Covid Pandemic% Gain to Breakeven% Gain to Breakeven52.4%51.3%
2020 Covid PandemicTime to BreakevenTime to Breakeven308 days148 days
2018 Correction2018 Correction  
2018 Correction% Loss% Loss-37.5%-19.8%
2018 Correction% Gain to Breakeven% Gain to Breakeven60.0%24.7%
2018 CorrectionTime to BreakevenTime to BreakevenNot Fully Recovered days120 days

Compare to ALNY, RARE, SRPT, NTLA, ACSB


In The Past

Ionis Pharmaceuticals's stock fell -59.8% during the 2022 Inflation Shock from a high on 1/25/2021. A -59.8% loss requires a 149.0% gain to breakeven.

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Asset Allocation

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About Ionis Pharmaceuticals (IONS)

Better Bets than Ionis Pharmaceuticals (IONS)

Latest Trefis Analyses

Trade Ideas

Select past ideas related to IONS. For more, see Trefis Trade Ideas.

Unique KeyDateTickerCompanyCategoryTrade Strategy6M Fwd Rtn12M Fwd Rtn12M Max DD
CRL_11142025_Dip_Buyer_FCFYield11142025CRLCharles River Laboratories InternationalDip BuyDB | FCFY OPMDip Buy with High FCF Yield and High Margin
Buying dips for companies with high FCF yield and meaningfully high operating margin
16.3%16.3%-3.7%
GDRX_11142025_Dip_Buyer_High_CFO_Margins_ExInd_DE11142025GDRXGoodRxDip BuyDB | CFO/Rev | Low D/EDip Buy with High Cash Flow Margins
Buying dips for companies with significant cash flows from operations and reasonable debt / market cap
-7.1%-7.1%-11.8%
ASTH_11142025_Dip_Buyer_High_FCF_Yield_ExInd_DE_RevG11142025ASTHAstrana HealthDip BuyDB | FCF Yield | Low D/EDip Buy with High Free Cash Flow Yield
Buying dips for companies with significant free cash flow yield (FCF / Market Cap) and reasonable debt / market cap
3.6%3.6%-5.5%
SGRY_11142025_Dip_Buyer_High_FCF_Yield_ExInd_DE_RevG11142025SGRYSurgery PartnersDip BuyDB | FCF Yield | Low D/EDip Buy with High Free Cash Flow Yield
Buying dips for companies with significant free cash flow yield (FCF / Market Cap) and reasonable debt / market cap
1.6%1.6%-1.4%
TFX_11072025_Dip_Buyer_FCFYield11072025TFXTeleflexDip BuyDB | FCFY OPMDip Buy with High FCF Yield and High Margin
Buying dips for companies with high FCF yield and meaningfully high operating margin
14.1%14.1%-5.1%
Unique KeyDateTickerCompanyCategoryTrade Strategy6M Fwd Rtn12M Fwd Rtn12M Max DD
CRL_11142025_Dip_Buyer_FCFYield11142025CRLCharles River Laboratories InternationalDip BuyDB | FCFY OPMDip Buy with High FCF Yield and High Margin
Buying dips for companies with high FCF yield and meaningfully high operating margin
16.3%16.3%-3.7%
GDRX_11142025_Dip_Buyer_High_CFO_Margins_ExInd_DE11142025GDRXGoodRxDip BuyDB | CFO/Rev | Low D/EDip Buy with High Cash Flow Margins
Buying dips for companies with significant cash flows from operations and reasonable debt / market cap
-7.1%-7.1%-11.8%
ASTH_11142025_Dip_Buyer_High_FCF_Yield_ExInd_DE_RevG11142025ASTHAstrana HealthDip BuyDB | FCF Yield | Low D/EDip Buy with High Free Cash Flow Yield
Buying dips for companies with significant free cash flow yield (FCF / Market Cap) and reasonable debt / market cap
3.6%3.6%-5.5%
SGRY_11142025_Dip_Buyer_High_FCF_Yield_ExInd_DE_RevG11142025SGRYSurgery PartnersDip BuyDB | FCF Yield | Low D/EDip Buy with High Free Cash Flow Yield
Buying dips for companies with significant free cash flow yield (FCF / Market Cap) and reasonable debt / market cap
1.6%1.6%-1.4%
TFX_11072025_Dip_Buyer_FCFYield11072025TFXTeleflexDip BuyDB | FCFY OPMDip Buy with High FCF Yield and High Margin
Buying dips for companies with high FCF yield and meaningfully high operating margin
14.1%14.1%-5.1%

Recent Active Movers

Recent Active Movers

More From Trefis

Peer Comparisons for Ionis Pharmaceuticals

Peers to compare with:

Financials

IONSALNYBIIBVRTXSRPTARWRMedian
NameIonis Ph.Alnylam .Biogen Vertex P.Sarepta .Arrowhea. 
Mkt Price77.08392.10172.10449.5221.1464.80124.59
Mkt Cap12.351.525.2114.92.18.918.8
Rev LTM9673,21010,06611,7232,4148292,812
Op Inc LTM-2782652,492-92-86986
FCF LTM-3092212,2623,337-389157189
FCF 3Y Avg-420571,6862,064-495-259-101
CFO LTM-2472662,4543,718-245180223
CFO 3Y Avg-3801081,9802,419-379-146-19

Growth & Margins

IONSALNYBIIBVRTXSRPTARWRMedian
NameIonis Ph.Alnylam .Biogen Vertex P.Sarepta .Arrowhea. 
Rev Chg LTM20.4%53.2%4.8%10.3%47.1%23,258.2%33.8%
Rev Chg 3Y Avg7.1%51.4%-0.9%10.5%40.6%7,719.5%25.5%
Rev Chg Q17.1%149.3%2.8%11.0%-14.5%-11.0%
QoQ Delta Rev Chg LTM2.4%30.4%0.7%2.7%-2.7%44.8%2.5%
Op Mgn LTM-28.8%8.2%24.8%-0.8%-3.6%11.9%3.7%
Op Mgn 3Y Avg-55.1%-7.1%22.5%26.2%-11.6%-5,666.8%-9.3%
QoQ Delta Op Mgn LTM-0.5%15.6%0.7%1.0%-3.5%30.7%0.8%
CFO/Rev LTM-25.5%8.3%24.4%31.7%-10.1%21.6%15.0%
CFO/Rev 3Y Avg-52.4%3.7%20.0%23.1%-26.8%-4,358.9%-11.5%
FCF/Rev LTM-32.0%6.9%22.5%28.5%-16.1%18.9%12.9%
FCF/Rev 3Y Avg-57.4%1.3%17.0%19.8%-33.7%-5,712.2%-16.2%

Valuation

IONSALNYBIIBVRTXSRPTARWRMedian
NameIonis Ph.Alnylam .Biogen Vertex P.Sarepta .Arrowhea. 
Mkt Cap12.351.525.2114.92.18.918.8
P/S10.818.72.08.50.810.89.7
P/EBIT-60.0460.09.522.4-8.463.416.0
P/E-40.81,375.912.827.2-7.1-5,477.92.8
P/CFO-42.3225.58.426.9-7.949.817.6
Total Yield-2.5%0.1%7.8%3.7%-14.1%-0.0%0.0%
Dividend Yield0.0%0.0%0.0%0.0%0.0%0.0%0.0%
FCF Yield 3Y Avg-6.0%0.0%6.7%2.3%-10.0%-11.1%-3.0%
D/E0.10.00.30.00.60.00.1
Net D/E-0.1-0.00.1-0.00.2-0.1-0.0

Returns

IONSALNYBIIBVRTXSRPTARWRMedian
NameIonis Ph.Alnylam .Biogen Vertex P.Sarepta .Arrowhea. 
1M Rtn5.2%-14.9%4.5%3.6%20.5%61.4%4.9%
3M Rtn26.0%-13.2%18.8%16.1%24.0%122.5%21.4%
6M Rtn108.3%25.5%36.0%0.2%1.8%314.9%30.8%
12M Rtn104.6%59.0%14.2%-4.2%-83.2%191.0%36.6%
3Y Rtn99.4%65.5%-39.6%47.5%-82.9%104.0%56.5%
1M Excs Rtn4.5%-15.6%3.8%2.8%19.8%60.7%4.1%
3M Excs Rtn23.5%-14.6%18.3%14.8%12.8%104.3%16.5%
6M Excs Rtn95.9%13.2%23.6%-12.1%-10.6%302.5%18.4%
12M Excs Rtn99.5%48.7%3.6%-14.1%-94.0%185.5%26.2%
3Y Excs Rtn33.0%-2.2%-109.2%-25.4%-151.0%35.0%-13.8%

Financials

Segment Financials

Revenue by Segment

$ Mil20242023202220212020
Ionis operations788    
Commercial revenue 303342365 
Research and development revenue 284468365 
Akcea Therapeutics    489
Elimination of Intercompany Activity    -225
Ionis Core    859
Total7885878107291,123


Net Income by Segment
$ Mil20242023202220212020
Ionis operations-366    
Total-366    


Price Behavior

Short Interest

Short Interest: As Of Date11282025
Short Interest: Shares Quantity15,626,208
Short Interest: % Change Since 111520259.9%
Average Daily Volume2,624,122
Days-to-Cover Short Interest5.95
Basic Shares Quantity159,765,000
Short % of Basic Shares9.8%

Earnings Returns History

Expand for More

 Forward Returns
Earnings Date1D Returns5D Returns21D Returns
10/29/2025-2.3%-0.9%12.4%
7/30/20254.6%3.8%3.1%
4/30/20253.0%6.9%12.2%
2/19/2025-0.4%-0.3%4.4%
11/6/20240.6%-2.7%-5.3%
8/1/20243.8%-5.4%0.9%
5/7/2024-3.2%-8.2%-5.7%
2/21/2024-1.8%6.9%-3.5%
...
SUMMARY STATS   
# Positive131212
# Negative111212
Median Positive1.9%3.9%10.3%
Median Negative-3.0%-4.3%-7.4%
Max Positive5.7%7.9%20.9%
Max Negative-5.0%-12.6%-22.8%

SEC Filings

Expand for More

Report DateFiling DateFiling
93020251029202510-Q 9/30/2025
6302025730202510-Q 6/30/2025
3312025430202510-Q 3/31/2025
12312024219202510-K 12/31/2024
93020241106202410-Q 9/30/2024
6302024801202410-Q 6/30/2024
3312024507202410-Q 3/31/2024
12312023221202410-K 12/31/2023
93020231102202310-Q 9/30/2023
6302023809202310-Q 6/30/2023
3312023503202310-Q 3/31/2023
12312022222202310-K 12/31/2022
93020221109202210-Q 9/30/2022
6302022809202210-Q 6/30/2022
3312022504202210-Q 3/31/2022
12312021225202210-K 12/31/2021