Spero Therapeutics (SPRO) Options Chain
NASDAQ: SPROHealth CareBiotechnology: Pharmaceutical PreparationsUSD
At close: Oct 8, 4:00 PM ET · Delayed 15 min
Expiration date
- Expiration
- Oct 16, 2026
- Days to expiration
- 7
- Share price
- $1.14
- Put/call ratio (OI)
- 0.14
- Put/call ratio (volume)
- 0.25
- Expected move
- ±$0.0395
- Open interest (C / P)
- 4.27K / 616
SPRO options summary
The SPRO options chain for the October 16, 2026 expiration lists 5 call and 5 put contracts, with 7 days until expiration. Open interest stands at 4,270 calls and 616 puts, a put/call ratio of 0.14, which is tilted bullish, with calls outnumbering puts. At-the-money implied volatility near the $1.00 strike is 25.0%, which implies the market expects a move of about ±$0.0395 (3.5%) in Spero Therapeutics stock by expiration.
The most open interest sits at the $5.00 call (1.82K contracts) and the $2.50 put (595 contracts).
Summary generated from market data by MetaCap's automated system. Methodology
SPRO options chain · October 16, 2026
| Calls | Puts | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Last | Bid | Ask | Strike | Bid | Ask | Last | |||||
| — | — | — | 0.50 | 0.00 | 0.00 | 0.05 | |||||
| — | — | — | 1.00 | 0.00 | 0.00 | 0.05 | |||||
| 0.05 | 0.00 | 0.00 | 1.50 | — | — | — | |||||
| 0.09 | 0.00 | 0.00 | 2.00 | 0.00 | 0.00 | 0.62 | |||||
| 0.05 | 0.00 | 0.00 | 2.50 | 0.00 | 0.00 | 1.34 | |||||
| 0.01 | 0.00 | 0.00 | 5.00 | 0.00 | 0.00 | 2.90 | |||||
| 0.10 | 0.00 | 0.00 | 7.50 | — | — | — | |||||
In-the-money callsIn-the-money puts. IV = implied volatility, OI = open interest (contracts). Each contract covers 100 shares. Quotes delayed at least 15 minutes.
Frequently asked questions
What is the SPRO put/call ratio?
For the October 16, 2026 expiration, the SPRO put/call ratio based on open interest is 0.14 (616 puts vs 4,270 calls), and 0.25 based on today's volume. A ratio above 1 means more puts than calls.
What is SPRO's implied volatility?
At-the-money implied volatility for SPRO options expiring October 16, 2026 is about 25.0%, an annualized estimate of how much the market expects Spero Therapeutics stock to move.
How many SPRO option expiration dates are there?
SPRO has 4 listed expiration dates, from Oct 16, 2026 to Apr 16, 2027.
What does "in the money" mean?
A call is in the money when the strike price is below the current share price; a put is in the money when the strike is above it. In-the-money contracts have intrinsic value and are shaded in the table.