STOK Bull Call Spread Strategy
STOK (Stoke Therapeutics, Inc.), in the Healthcare sector, (Biotechnology industry), listed on NASDAQ.
Stoke Therapeutics, Inc., an early-stage biopharmaceutical company, develops novel antisense oligonucleotide (ASO) medicines to treat the underlying causes of severe genetic diseases in the United States. The company utilizes its proprietary Targeted Augmentation of Nuclear Gene Output to design ASOs to precisely upregulate protein expression. Its lead clinical candidate is STK-001, which is in phase I/IIa clinical trial to treat Dravet syndrome, a severe and progressive genetic epilepsy; and STK-002, which is in preclinical stage for the treatment of autosomal dominant optic atrophy. It had entered into a license and collaboration agreement with Acadia Pharmaceuticals Inc. for the discovery, development, and commercialization of novel RNA-based medicines for the treatment of severe and rare genetic neurodevelopmental diseases of the central nervous system. The company was formerly known as ASOthera Pharmaceuticals, Inc. and changed its name to Stoke Therapeutics, Inc. in May 2016. Stoke Therapeutics, Inc. was incorporated in 2014 and is headquartered in Bedford, Massachusetts.
STOK (Stoke Therapeutics, Inc.) trades in the Healthcare sector, specifically Biotechnology, with a market capitalization of approximately $1.97B, a beta of 1.20 versus the broader market, a 52-week range of 8.97-40.22, average daily share volume of 728K, a public-listing history dating back to 2019, approximately 128 full-time employees. These structural characteristics shape how STOK stock options price implied volatility around earnings windows, capital events, and macro-driven sector rotations.
A beta of 1.20 places STOK roughly in line with broader market moves, so the strategy payoff and realized volatility track the index-equivalent baseline.
What is a bull call spread on STOK?
A bull call spread buys an at-the-money call and sells an out-of-the-money call at a higher strike for defined risk and defined reward bounded by the strike width.
Current STOK snapshot
As of May 15, 2026, spot at $30.09, ATM IV 85.70%, IV rank 24.35%, expected move 24.57%. The bull call spread on STOK below is built from the same end-of-day chain, with strikes snapped to listed contracts and premiums pulled from the bid/ask midpoint at a 34-day expiry.
Why this bull call spread structure on STOK specifically: STOK IV at 85.70% is on the cheap side of its 1-year range, which favors premium-buying structures like a STOK bull call spread, with a market-implied 1-standard-deviation move of approximately 24.57% (roughly $7.39 on the underlying). The 34-day window matched to the front-month expiry keeps theta exposure bounded while still capturing the post-snapshot move; longer-dated STOK expiries trade a higher absolute premium for lower per-day decay. Position sizing on STOK should anchor to the underlying notional of $30.09 per share and to the trader's directional view on STOK stock.
STOK bull call spread setup
The STOK bull call spread below is built from the end-of-day chain, with each option leg priced at the bid/ask midpoint of its listed strike. With STOK near $30.09, the first option leg uses a $30.09 strike; additional legs (when the strategy has them) anchor to spot-relative offsets. Premiums come from the bid/ask midpoint on the listed STOK chain at a 34-day expiry; the cross-strike IV skew is reflected directly in the per-leg values rather than approximated. Quantity sizing assumes one contract per option leg (or 100 STOK shares for the stock leg in covered calls and collars).
| Action | Type | Strike / Basis | Premium (est) |
|---|---|---|---|
| Buy 1 | Call | $30.09 | N/A |
| Sell 1 | Call | $31.59 | N/A |
STOK bull call spread risk and reward
- Net Premium / Debit
- N/A
- Max Profit (per contract)
- Unbounded
- Max Loss (per contract)
- Unbounded
- Breakeven(s)
- None on modeled curve
- Risk / Reward Ratio
- N/A
Max profit equals strike width minus net debit times 100; max loss equals net debit times 100. Breakeven is long-call strike plus net debit.
STOK bull call spread payoff curve
Modeled P&L at expiration across a range of underlying prices for the bull call spread on STOK. Each row is one sampled price point from the computed payoff curve; the full curve uses 200 price points internally before being summarized into 10 rows here.
When traders use bull call spread on STOK
Bull call spreads on STOK reduce the cost of a bullish STOK stock position by selling a higher-strike call; suited to moderate-move theses where price reaches but does not vastly exceed the short strike.
STOK thesis for this bull call spread
The market-implied 1-standard-deviation range for STOK extends from approximately $22.70 on the downside to $37.48 on the upside. A STOK bull call spread caps both the risk and the reward of a bullish position; relative to an outright long call on STOK, the spread reduces the cost basis but limits the maximum profit to the strike width minus net debit. Current STOK IV rank near 24.35% sits in the lower third of its 1-year distribution, where IV often re-expands toward the mean; this favors premium-buying structures and disadvantages premium-selling structures on STOK at 85.70%. As a Healthcare name, STOK options can move on sector-level news flow (peer earnings, regulatory updates, industry-specific macro data) in addition to STOK-specific events.
STOK bull call spread positions are structurally moderately bullish; the modeled P&L assumes European-style exercise at expiration and ignores early assignment, transaction costs, dividends paid before expiry on the stock leg (when present), and the bid-ask spread on the listed chain. STOK positions also carry Healthcare sector concentration risk; news flow inside the sector (peer earnings, regulatory shifts, supply-chain headlines) can move STOK alongside the broader basket even when STOK-specific fundamentals are unchanged. Long-premium structures like a bull call spread on STOK are particularly exposed to IV-crush risk through scheduled events (earnings, FDA decisions, central-bank meetings) where IV typically contracts post-event regardless of the directional outcome. Always rebuild the position from current STOK chain quotes before placing a trade.
Frequently asked questions
- What is a bull call spread on STOK?
- A bull call spread on STOK is the bull call spread strategy applied to STOK (stock). The strategy is structurally moderately bullish: A bull call spread buys an at-the-money call and sells an out-of-the-money call at a higher strike for defined risk and defined reward bounded by the strike width. With STOK stock trading near $30.09, the strikes shown on this page are snapped to the nearest listed STOK chain strike and the premiums come straight from the end-of-day bid/ask midpoint.
- How are STOK bull call spread max profit and max loss calculated?
- Max profit equals strike width minus net debit times 100; max loss equals net debit times 100. Breakeven is long-call strike plus net debit. For the STOK bull call spread priced from the end-of-day chain at a 30-day expiry (ATM IV 85.70%), the computed maximum profit is unbounded per contract and the computed maximum loss is unbounded per contract. Live intraday quotes will differ as the chain moves through the trading session.
- What is the breakeven for a STOK bull call spread?
- The breakeven for the STOK bull call spread priced on this page is no defined breakeven on the modeled curve at expiration, derived from end-of-day chain premiums. Breakeven is the underlying price at which the strategy's P&L crosses zero ignoring transaction costs and assignment risk. The current STOK market-implied 1-standard-deviation expected move is approximately 24.57%; if the move sits well outside the breakeven distance, the structure's risk-reward becomes correspondingly tighter.
- When should you consider a bull call spread on STOK?
- Bull call spreads on STOK reduce the cost of a bullish STOK stock position by selling a higher-strike call; suited to moderate-move theses where price reaches but does not vastly exceed the short strike.
- How does current STOK implied volatility affect this bull call spread?
- STOK ATM IV is at 85.70% with IV rank near 24.35%, which is on the low end of its 1-year range. Premium-buying structures (long call, long put, debit spreads) are relatively cheap in this regime; premium-selling structures collect less credit per unit risk.