Spero Therapeutics, Inc SPRO

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Spero Therapeutics, Inc. - Common Stock · Company · Nasdaq · Healthcare / Biotechnology

Paper trade (simulated — no real money)

Fill: USD 1.1100 · FX 1 USD = 1.277900 SGD · about SGD 1.4185 per unit

Sign in to practise with simulated trades before investing real money. USD fills are converted into the SGD portfolio at the displayed rate.

Announcement types: (default: consequential filings)
Results & current reports
Capital markets
Ownership & governance

USD closing-price chart (daily close from yfinance · Last year)

USD 2.21 → 1.11 · -49.8%
2.9802.0401.100 1,2 3 4 5,6 7 8,9 10,11 12 13 14 15,16 17,18 Oct 25Jan 26Apr 26Jul 26Oct 26

Numbered dotted lines mark the filtered filings under Announcement Events below.

Price & SEC Filing History 24 Oct 2025 — 25 Oct 2026 (Last year)

Daily Nasdaq prices are sourced from yfinance. Yellow highlighting marks an intraday rise or a gap up between adjacent trading sessions. SEC acceptance times are converted to US Eastern time: pre-market filings appear below that day’s OHLCV row; filings accepted after the 09:30 ET open appear above it. The SEC does not publish an exact first-public-availability timestamp, so acceptance time is the best available proxy.

Weekend
Weekend
1.1300 1.1300 1.1000 1.1100 316,181
1.1600 1.1700 1.1300 1.1300 201,800
1.2100 1.2200 1.1650 1.1700 265,700
1.1200 1.2400 1.1100 1.2200 678,800
1.0900 1.1300 1.0900 1.1200 203,000
Weekend
Weekend
1.1400 1.1700 1.0900 1.1000 361,300
1.1200 1.1400 1.1100 1.1300 233,800
1.1500 1.1700 1.1100 1.1200 696,500
1.1900 1.2030 1.1500 1.1500 272,500
1.2000 1.2200 1.1650 1.1800 414,100
Weekend
Weekend
1.1400 1.2100 1.1300 1.2000 438,800
1.2000 1.2200 1.1300 1.1400 718,900
1.1900 1.1900 1.1600 1.1700 233,600
1.2100 1.2360 1.1800 1.1900 347,000
1.1700 1.2000 1.1500 1.1600 935,700
Weekend
Weekend
1.2600 1.2660 1.1710 1.1900 906,900
1.2200 1.3100 1.1950 1.2600 1,039,200
1.2100 1.2900 1.2000 1.2100 557,900
1.2000 1.2200 1.1700 1.2000 334,900
1.2200 1.2200 1.1750 1.1900 393,100
Weekend
Weekend
1.2700 1.2900 1.2100 1.2300 541,800
1.2500 1.2900 1.2400 1.2500 473,900
1.3600 1.3980 1.2400 1.2600 1,402,900
1.3000 1.4400 1.2800 1.3600 7,759,500
1.1400 1.1500 1.1200 1.1400 319,100
Weekend
Weekend
1.1200 1.2100 1.1150 1.1300 501,400
1.1400 1.1400 1.1140 1.1200 180,100
1.1200 1.1400 1.1000 1.1100 439,600
1.1400 1.1510 1.1100 1.1300 224,300
1.1300 1.1600 1.1300 1.1400 266,100
Weekend
Weekend
1.1300 1.1500 1.1300 1.1300 308,600
1.1800 1.1800 1.1200 1.1200 569,300
1.2000 1.2100 1.1700 1.1700 367,100
1.2100 1.2200 1.1900 1.1900 348,400
No trading
Weekend
Weekend
1.2000 1.2200 1.1850 1.2100 362,900
1.2200 1.2300 1.2010 1.2200 203,300
1.2000 1.2390 1.2000 1.2200 169,500
1.2200 1.2200 1.1800 1.2000 382,300
1.2000 1.2300 1.2000 1.2200 330,200
Weekend
Weekend
18 · 8-K After market open · 13:25 ET 8-K ↗ 17 · S-3 After market open · 13:04 ET S-3 ↗
1.2100 1.2200 1.1810 1.2000 312,400
1.2200 1.2300 1.1800 1.2100 538,100
1.2200 1.2280 1.2000 1.2200 154,700
1.2300 1.2600 1.2000 1.2300 645,500
1.2200 1.2400 1.2000 1.2150 367,300
Weekend
Weekend
1.2200 1.2460 1.2100 1.2200 359,100
1.2200 1.2700 1.2000 1.2100 558,800
1.2000 1.2400 1.1920 1.2300 480,200
1.2000 1.2000 1.1750 1.2000 477,400
1.2100 1.2400 1.1900 1.1900 299,000
Weekend
Weekend
1.2600 1.2600 1.1940 1.2300 744,500
1.2600 1.3000 1.2100 1.2400 1,292,900
16 · 8-K After-hours · 16:09 ET 8-K ↗ 15 · 10-Q After-hours · 16:03 ET 10-Q ↗
1.2400 1.2450 1.1850 1.1900 774,600
1.2400 1.2500 1.2100 1.2300 364,100
1.2500 1.2760 1.2250 1.2300 350,800
Weekend
Weekend
1.2700 1.2800 1.2400 1.2600 459,000
1.2600 1.2750 1.2300 1.2700 974,700
1.2500 1.2800 1.2100 1.2600 574,900
1.1500 1.2500 1.1500 1.2300 752,000
1.1900 1.2200 1.1250 1.1500 1,373,000
Weekend
Weekend
1.2000 1.2140 1.1700 1.1700 824,600
1.2000 1.2200 1.1750 1.2000 486,600
1.2000 1.2100 1.1600 1.1900 1,055,500
1.1800 1.2800 1.1500 1.1950 1,602,400
1.2000 1.2300 1.1600 1.1800 1,346,400
Weekend
Weekend
1.1400 1.2300 1.0800 1.1900 11,767,500
1.2800 1.2800 1.1000 1.1600 3,732,600
1.3800 1.4100 1.2500 1.2700 1,990,400
1.4300 1.4400 1.3700 1.3800 2,181,800
1.5700 1.5700 1.4100 1.4400 1,718,800
Weekend
Weekend
1.5200 1.6350 1.5000 1.5800 1,249,300
1.6800 1.6850 1.5150 1.5700 2,627,700
1.7100 1.7100 1.6300 1.7000 1,425,300
2.1700 2.3400 1.6700 1.7000 11,306,800
14 · 8-K Pre-market · 06:30 ET 8-K ↗
2.1100 2.1900 2.0700 2.1800 704,000
Weekend
Weekend
2.1200 2.1570 2.0500 2.1000 481,700
2.1900 2.1950 2.1200 2.1200 369,800
2.1400 2.2300 2.1250 2.1700 303,900
2.1600 2.1950 2.1200 2.1600 879,800
2.1700 2.2050 2.1500 2.1900 372,700
Weekend
Weekend
No trading
2.2300 2.2800 2.1500 2.2000 629,500
2.2100 2.2650 2.2100 2.2200 397,500
2.2600 2.2850 2.2000 2.2100 435,200
2.2600 2.3290 2.2500 2.2600 517,900
Weekend
Weekend
2.0300 2.3250 2.0100 2.2600 2,222,000
13 · 8-K After-hours · 17:08 ET 8-K ↗
2.1200 2.1300 2.0200 2.0200 1,142,300
2.1500 2.2300 2.1000 2.1000 893,800
2.1600 2.2300 2.1500 2.1500 609,700
12 · 8-K After-hours · 16:05 ET 8-K ↗
2.2750 2.3600 2.1600 2.2100 2,271,200
Weekend
Weekend
No trading
2.5100 2.5100 2.1500 2.2800 7,195,300
2.8700 3.0500 1.9500 2.1100 11,185,600
2.9400 2.9800 2.7500 2.7700 1,432,200
2.9300 2.9660 2.8500 2.9100 934,400
Weekend
Weekend
2.7200 2.8500 2.7000 2.8500 623,700
2.5500 2.7600 2.4800 2.7000 1,156,400
2.6200 2.6350 2.5050 2.5400 762,500
2.7800 2.8100 2.5200 2.5700 1,129,100
2.8400 2.8700 2.7300 2.7400 649,000
Weekend
Weekend
3.0010 3.0010 2.7600 2.8200 756,300
2.7900 3.0670 2.7800 2.9800 1,026,100
2.8600 2.8700 2.7700 2.8000 775,500
2.8100 2.8700 2.7600 2.8300 606,000
2.8300 2.8890 2.7900 2.8300 649,000
Weekend
Weekend
2.9200 2.9200 2.7500 2.8300 1,338,900
2.9300 3.0000 2.8950 2.9000 790,900
2.8600 3.0800 2.8100 2.9300 1,773,900
2.8000 2.9450 2.7600 2.8600 1,516,000
No trading
Weekend
Weekend
2.7100 2.8500 2.6850 2.7600 545,500
2.6300 2.7050 2.5600 2.6900 433,200
2.5900 2.6450 2.5500 2.6300 320,200
2.5200 2.6200 2.5000 2.5900 323,200
2.7700 2.7900 2.5700 2.5800 917,900
Weekend
Weekend
2.7100 2.8850 2.6900 2.7900 939,000
2.4400 2.7600 2.3700 2.7600 1,606,700
11 · 10-Q After-hours · 16:05 ET 10-Q ↗ 10 · 8-K After-hours · 16:02 ET 8-K ↗
2.5600 2.5600 2.4250 2.4400 675,000
2.5100 2.5580 2.4800 2.5400 350,900
2.6200 2.6700 2.5400 2.5500 431,900
Weekend
Weekend
2.5200 2.5800 2.4900 2.5600 356,000
2.5400 2.6180 2.4950 2.5100 566,200
2.4700 2.5650 2.4400 2.5300 620,300
2.5100 2.5850 2.4100 2.4200 506,900
2.5000 2.6080 2.4610 2.5000 462,300
Weekend
Weekend
2.5400 2.6300 2.4750 2.4800 494,400
2.5000 2.5800 2.5000 2.5100 363,900
2.6500 2.6600 2.4710 2.5300 828,500
2.6800 2.7300 2.6700 2.6700 219,100
9 · DEFA14A After-hours · 16:39 ET DEFA14A ↗ 8 · DEF 14A After-hours · 16:30 ET DEF 14A ↗
2.7400 2.7500 2.6650 2.6700 322,700
Weekend
Weekend
2.8200 2.8200 2.7400 2.7400 346,500
2.8600 2.9100 2.7900 2.8000 297,000
2.8400 2.9250 2.8400 2.8600 319,700
2.8200 2.8200 2.7400 2.8000 266,100
2.7300 2.8600 2.7130 2.8400 395,800
Weekend
Weekend
2.7100 2.7800 2.6500 2.7500 381,200
2.6400 2.7100 2.6200 2.6800 552,100
2.7800 2.8000 2.6300 2.6400 696,100
2.8400 2.8800 2.7600 2.7800 603,700
7 · PRE 14A After-hours · 17:26 ET PRE 14A ↗
2.6700 2.8600 2.6700 2.7800 614,600
Weekend
Weekend
2.8000 2.8000 2.6250 2.6700 786,900
2.7200 2.8000 2.6700 2.7800 450,200
2.7000 2.7500 2.6050 2.7200 426,800
2.5900 2.6900 2.4800 2.6700 693,200
2.4400 2.6100 2.4400 2.6100 478,700
Weekend
Weekend
No trading
2.4100 2.4500 2.3800 2.4300 214,400
2.3500 2.4800 2.3400 2.4500 402,200
2.2900 2.3550 2.2100 2.3400 485,400
2.3880 2.4300 2.2400 2.2400 314,000
Weekend
Weekend
2.3000 2.4400 2.2800 2.3300 498,700
6 · 8-K After-hours · 16:10 ET 8-K ↗ 5 · 10-K After-hours · 16:05 ET 10-K ↗
2.3900 2.4800 2.3400 2.3700 482,600
2.3900 2.4600 2.3660 2.4100 189,300
2.2920 2.4700 2.2900 2.3700 395,000
2.3700 2.4090 2.3300 2.3500 176,400
Weekend
Weekend
2.4700 2.4700 2.3500 2.3700 235,800
2.4500 2.4800 2.3800 2.4700 201,700
2.5800 2.5800 2.4000 2.4600 351,200
2.5800 2.7000 2.5700 2.5800 389,600
2.5700 2.6200 2.5510 2.5900 214,800
Weekend
Weekend
2.5800 2.6000 2.5080 2.5800 200,300
2.5600 2.6400 2.5000 2.5900 344,900
2.4300 2.6000 2.4000 2.5900 619,800
2.3100 2.4600 2.3100 2.4500 540,300
2.2700 2.3550 2.2200 2.3200 377,500
Weekend
Weekend
2.2700 2.3100 2.2500 2.3000 142,100
2.2600 2.3000 2.2200 2.2900 178,400
2.2100 2.3050 2.2000 2.2900 315,100
2.1300 2.2100 2.1100 2.1900 228,800
2.1200 2.2100 2.1200 2.1900 195,700
Weekend
Weekend
2.2200 2.2700 2.1500 2.1700 290,200
2.2200 2.2500 2.1650 2.2100 273,200
2.2200 2.2550 2.1900 2.2200 236,700
2.2300 2.2550 2.1500 2.2300 682,700
2.3200 2.3300 2.2000 2.2400 565,900
Weekend
Weekend
2.3800 2.3900 2.2800 2.3000 159,000
2.3300 2.4100 2.3200 2.4000 172,800
2.3500 2.4050 2.3150 2.3300 265,900
2.3900 2.4000 2.3000 2.3500 283,200
No trading
Weekend
Weekend
2.3800 2.4370 2.3800 2.3900 136,800
2.3700 2.4100 2.3150 2.3800 104,200
2.3700 2.4290 2.3200 2.3700 138,200
2.4000 2.4000 2.3500 2.3600 173,600
2.4000 2.4000 2.2750 2.3600 349,000
Weekend
Weekend
2.3100 2.4300 2.3050 2.4200 1,027,400
2.2500 2.4900 2.2500 2.3000 748,700
2.2600 2.3200 2.1850 2.2900 937,800
2.2100 2.2900 2.1000 2.1400 440,500
2.1500 2.2650 2.1380 2.2300 277,100
Weekend
Weekend
4 · 8-K After-hours · 17:01 ET 8-K ↗
2.2400 2.2500 2.1800 2.1900 244,500
2.2300 2.3000 2.2200 2.2500 168,900
2.3600 2.3700 2.2200 2.2300 369,200
2.4500 2.4500 2.3450 2.3700 244,600
2.4300 2.4650 2.3690 2.4500 181,700
Weekend
Weekend
2.4400 2.4620 2.4150 2.4400 151,700
2.3400 2.4600 2.3200 2.4500 299,600
2.3800 2.4050 2.3200 2.3600 160,200
2.4000 2.4000 2.3100 2.3800 276,600
No trading
Weekend
Weekend
2.4000 2.4200 2.3400 2.4100 266,100
2.5000 2.5100 2.3900 2.4000 222,300
2.4500 2.5200 2.4100 2.5100 215,600
2.5100 2.5200 2.4450 2.4500 168,000
2.5300 2.5450 2.4800 2.5100 167,800
Weekend
Weekend
2.5700 2.5700 2.5200 2.5500 150,700
2.5900 2.6000 2.5100 2.5700 284,600
2.5100 2.6550 2.4900 2.6000 322,200
2.4400 2.5200 2.4150 2.5100 283,200
2.3800 2.4680 2.3790 2.4300 304,600
Weekend
Weekend
2.3200 2.3700 2.3000 2.3500 247,200
No trading
2.2700 2.3300 2.2700 2.3300 218,100
2.2900 2.3000 2.2700 2.2700 195,500
2.3100 2.3200 2.2700 2.3000 163,600
Weekend
Weekend
2.3300 2.3700 2.2700 2.3200 280,400
No trading
2.3200 2.3600 2.3100 2.3400 89,800
2.3600 2.4150 2.3100 2.3300 245,300
2.3200 2.3700 2.2900 2.3700 260,300
Weekend
Weekend
2.3500 2.4200 2.2800 2.3200 465,200
3 · 8-K Pre-market · 08:25 ET 8-K ↗
2.3300 2.3350 2.2800 2.2900 290,700
2.2900 2.3800 2.2900 2.3100 308,500
2.2900 2.3100 2.2550 2.2700 202,600
2.3300 2.3500 2.2850 2.2900 208,200
Weekend
Weekend
2.3600 2.3600 2.3000 2.3200 287,700
2.3300 2.3600 2.3100 2.3500 186,100
2.3400 2.3900 2.3100 2.3300 336,000
2.3100 2.3480 2.2550 2.3300 349,400
2.2900 2.3600 2.2700 2.3100 323,400
Weekend
Weekend
2.2900 2.3100 2.2500 2.2600 161,000
2.2700 2.3250 2.2400 2.2800 241,600
2.2100 2.2900 2.1800 2.2800 364,400
2.2800 2.2900 2.2000 2.2000 505,000
2.3300 2.3800 2.2600 2.2700 367,500
Weekend
Weekend
2.3500 2.4200 2.3300 2.4000 136,600
No trading
2.3500 2.3800 2.2800 2.3300 363,100
2.3700 2.3700 2.3000 2.3400 284,200
2.3400 2.4000 2.3300 2.3800 626,900
Weekend
Weekend
2.2200 2.3250 2.2100 2.3100 171,800
2.4000 2.4190 2.2300 2.2600 435,100
2.4700 2.4700 2.3320 2.3800 512,700
2.4000 2.4900 2.3700 2.4700 325,400
2.4100 2.5700 2.4100 2.4300 635,100
Weekend
Weekend
2.3900 2.4770 2.3300 2.4100 251,100
2 · 8-K After-hours · 17:18 ET 8-K ↗ 1 · 10-Q After-hours · 16:10 ET 10-Q ↗
2.6600 2.7170 2.4300 2.4400 881,800
2.6300 2.7500 2.6100 2.6600 752,600
2.5000 2.6550 2.5000 2.6200 675,200
2.4500 2.5700 2.4500 2.5000 481,900
Weekend
Weekend
2.3800 2.4600 2.3500 2.4600 514,700
2.4300 2.4700 2.3750 2.3900 603,700
2.3500 2.4800 2.3500 2.4300 596,100
2.3500 2.4700 2.3300 2.3500 706,100
2.4400 2.4650 2.3200 2.3800 447,700
Weekend
Weekend
2.3500 2.4750 2.3300 2.4300 493,300
2.3300 2.4400 2.3100 2.3600 332,800
2.3700 2.4000 2.3000 2.3300 433,900
2.2800 2.4200 2.2700 2.3800 585,800
2.2200 2.3000 2.2120 2.2900 296,200
Weekend
Weekend
2.2000 2.2450 2.1850 2.2100 451,700

Announcement Events

Each title opens the filing on the SEC website. Registered users can summarise the filing and up to seven relevant exhibits linked within the same SEC submission.

18 8-K 8-K (opens SEC filing in a new tab) After market open · 13:25 ET Summarise
17 S-3 S-3 (opens SEC filing in a new tab) After market open · 13:04 ET Summarise
16 8-K 8-K (opens SEC filing in a new tab) After-hours · 16:09 ET Summarise
15 10-Q 10-Q (opens SEC filing in a new tab) After-hours · 16:03 ET Summarise
14 8-K 8-K (opens SEC filing in a new tab) Pre-market · 06:30 ET Summarise
13 8-K 8-K (opens SEC filing in a new tab) After-hours · 17:08 ET Summarise
12 8-K 8-K (opens SEC filing in a new tab) After-hours · 16:05 ET Summarise
11 10-Q 10-Q (opens SEC filing in a new tab) After-hours · 16:05 ET Summarise
10 8-K 8-K (opens SEC filing in a new tab) After-hours · 16:02 ET Summarise
9 DEFA14A DEFA14A (opens SEC filing in a new tab) After-hours · 16:39 ET Summarise
8 DEF 14A DEF 14A (opens SEC filing in a new tab) After-hours · 16:30 ET Summarise
7 PRE 14A PRE 14A (opens SEC filing in a new tab) After-hours · 17:26 ET Summarise
6 8-K 8-K (opens SEC filing in a new tab) After-hours · 16:10 ET Summarise
5 10-K 10-K (opens SEC filing in a new tab) After-hours · 16:05 ET Summarise
4 8-K 8-K (opens SEC filing in a new tab) After-hours · 17:01 ET Summarise
3 8-K 8-K (opens SEC filing in a new tab) Pre-market · 08:25 ET Summarise
2 8-K 8-K (opens SEC filing in a new tab) After-hours · 17:18 ET Summarise
1 10-Q 10-Q (opens SEC filing in a new tab) After-hours · 16:10 ET Summarise