ARKG returned +76.9% and XBI +88.6% over 12 months. Here's what's inside the ACCE Biotech Catalysts index and why VRTX, SRPT, BMRN, LLY, and REGN anchor it.
Biotech has been one of the most rewarding sectors of the past twelve months. The SPDR S&P Biotech ETF (XBI) returned +88.6% over the last year. The ARK Genomic Revolution ETF (ARKG) posted +76.9%. The leveraged Direxion Daily S&P Biotech Bull 3X (LABU) returned +394.5%. The sector is moving, and the ACCE Biotech Catalysts index is built to capture the highest-conviction names within it.
Here is a full breakdown of what the index holds, how each position is sized, and what the underlying data says about the current setup.
What the Index Holds
The ACCE Biotech Catalysts index carries a NAV of 1075.83 as of July 2, 2026. Five names make up the bulk of the exposure:
- Vertex Pharmaceuticals (VRTX), 21%
- Sarepta Therapeutics (SRPT), 19%
- BioMarin Pharmaceutical (BMRN), 19%
- Eli Lilly (LLY), 17%
- Regeneron Pharmaceuticals (REGN), 15%
- Novo Nordisk (NVO), 9%
- Madrigal Pharmaceuticals (MDGL), 0% (monitoring position)
The top five names alone account for 91% of the index. This is a concentrated, high-conviction portfolio, not a diversified basket. The construction reflects a deliberate choice: own the companies with the clearest near-term catalysts and the strongest underlying business quality, rather than spreading exposure across dozens of speculative names.
The Quality Anchor: Why These Names
The index skews heavily toward profitable, cash-generative biotechs rather than pre-revenue clinical-stage bets. That is a meaningful distinction in a sector where most companies burn cash for years before generating a dollar of earnings.
Vertex Pharmaceuticals (VRTX) leads the index at 21%. Vertex has built a near-monopoly in cystic fibrosis treatments and is advancing programs in pain, kidney disease, and type 1 diabetes. Its business generates substantial free cash flow, and the pipeline is genuinely diversified across multiple large indications.
Eli Lilly (LLY) at 17% brings the index's largest-cap anchor. Lilly's GLP-1 franchise, anchored by tirzepatide across diabetes and obesity, has reshaped the company's revenue trajectory. The scale of the obesity market opportunity is difficult to overstate, and Lilly has manufacturing capacity coming online to match demand.
Regenerons (REGN) at 15% and BioMarin (BMRN) at 19% add complementary exposure. Regeneron's Dupixent franchise continues to expand into new indications, while BioMarin focuses on rare genetic diseases where pricing power is structurally high and competition is limited.
Sarepta Therapeutics (SRPT) at 19% is the highest-risk, highest-reward position. Sarepta's gene therapy programs for Duchenne muscular dystrophy represent a genuine platform, but the regulatory and commercial execution risk is real. The index weights it equally with BMRN, signaling confidence in the near-term catalyst pipeline.
Novo Nordisk (NVO) at 9% rounds out the core. Like Lilly, Novo's GLP-1 dominance gives the index two large-cap positions in the most commercially significant drug category of the decade.
The Broader Biotech Momentum Signal
The data from the broader ACCE universe reinforces the bullish read on biotech momentum. XBI carries an ACCE score of 97/100 with a Momentum subscore of 97. ARKG scores 97/100 on the same basis, with a 1-year return of +76.9%. LABU, the 3x leveraged biotech ETF, also scores 97/100 with a Momentum subscore of 97.
Three separate biotech instruments all scoring 97 on momentum simultaneously is not noise. It reflects a genuine sector rotation into healthcare and biotech that has been building since mid-2025.
Biogen (BIIB), which sits outside the index but is tracked in the ACCE universe, shows what the setup can look like at the individual stock level. Biogen carries an ACCE score of 74/100, with a Momentum subscore of 97 and a 1-year return of +61.6%. Its earnings grew +31.1% year-over-year, and the forward P/E sits at 15.5x. The recent alert flagging material 2026 R&D milestone charges is worth watching, but the underlying momentum profile is strong.
BridgeBio Pharma (BBIO) is another name on the radar. Its $1B financing across three pipeline launches, announced this week, signals that institutional capital is actively funding late-stage biotech programs. BBIO's revenue grew +66.8% year-over-year, and its 1-year return stands at +74.6%.
What the Index Is Not
The ACCE Biotech Catalysts index is not a bet on speculative genomics or early-stage CRISPR plays. The MDGL position at 0% is a monitoring allocation, not an active weight. Madrigal Pharmaceuticals, which won FDA approval for resmetirom in NASH, is being tracked as a potential addition but has not yet earned a full allocation.
The index also avoids the trap of chasing the highest-momentum names regardless of fundamentals. LABU returning +394.5% in a year is a momentum signal, not a quality signal. The Biotech Catalysts index is built around companies that generate or are approaching meaningful revenue, have defensible intellectual property, and carry identifiable near-term catalysts, not just price momentum.
Risks Worth Naming
Concentration is the primary structural risk. Five names at 91% of the index means a single regulatory setback, a clinical trial failure, or a pricing policy shift from CMS could move the NAV materially. Sarepta in particular carries binary event risk around its gene therapy programs.
The GLP-1 duopoly between Lilly and Novo also creates correlated exposure. Both names are in the index, and both face the same competitive threats from Amgen, Roche, and others developing next-generation obesity drugs. A meaningful clinical readout from a competitor could pressure both positions simultaneously.
Drug pricing legislation remains a background risk for the entire sector. The Inflation Reduction Act's Medicare negotiation provisions are already affecting certain drug categories, and further expansion of that framework would compress margins across the index's holdings.
The Setup Heading Into H2 2026
The sector momentum is real, the quality of the index's holdings is high, and the pipeline of catalysts across VRTX, SRPT, LLY, and REGN is dense enough to sustain investor attention through the back half of the year. The broader biotech ETF signals from XBI and ARKG suggest this is not a sector in the late stages of a momentum run but one that institutional capital is still actively entering.
The next twelve months will test whether the GLP-1 franchise can sustain its commercial trajectory as manufacturing scales and competition intensifies, and whether Sarepta's gene therapy platform can convert its regulatory approvals into durable revenue. Those two questions will do more to determine the index's NAV trajectory than any macro variable.
