Altimmune, Inc ALT

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

Paper trade (simulated — no real money)

Fill: USD 2.1200 · FX 1 USD = 1.277900 SGD · about SGD 2.7091 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 3.95 → 2.12 · -46.3%
6.1804.1502.120 1,2,3,4,5 6 7 8 9,10 11 12 13,14 15 16 17,18 19,20 21,22 23 24 25,26 27 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
2.1600 2.2000 2.0600 2.1200 2,599,076
2.2000 2.2450 2.1500 2.1700 3,089,600
2.3100 2.3500 2.1900 2.2300 4,501,800
2.2200 2.3200 2.2000 2.3000 2,305,600
2.2200 2.2600 2.1800 2.2300 2,611,300
Weekend
Weekend
2.3650 2.3690 2.1700 2.2000 4,240,400
2.3100 2.3800 2.2900 2.3600 3,344,400
2.4000 2.4100 2.2900 2.3100 5,623,700
2.5600 2.5600 2.4300 2.4300 3,713,400
2.5900 2.6250 2.5600 2.5600 2,158,700
Weekend
Weekend
2.6000 2.6400 2.5700 2.6100 2,677,700
2.6600 2.6600 2.5500 2.6000 4,929,500
2.6400 2.7400 2.6300 2.6600 3,168,200
2.7000 2.7000 2.6400 2.6700 7,623,300
2.7300 2.7470 2.6500 2.6700 3,839,500
Weekend
Weekend
2.8000 2.8100 2.7100 2.7350 4,243,900
2.8500 2.8500 2.7500 2.7600 3,589,100
2.9900 2.9900 2.8600 2.8600 4,922,500
27 · 8-K After market open · 11:03 ET 8-K ↗
2.9900 3.0060 2.9200 2.9700 2,561,000
3.0400 3.0700 2.9500 2.9600 3,357,500
Weekend
Weekend
3.0500 3.1100 3.0000 3.0600 2,858,800
3.1800 3.2000 2.9800 3.0400 3,685,800
3.4200 3.4250 3.1500 3.1900 4,531,500
3.3300 3.4100 3.2500 3.4100 4,003,300
3.3100 3.3400 3.2400 3.2700 3,516,200
Weekend
Weekend
3.2300 3.2600 3.1800 3.2500 12,175,800
3.3100 3.3500 3.2100 3.2400 3,456,600
3.2700 3.2900 3.1950 3.2400 3,328,800
3.3000 3.3100 3.2100 3.2300 2,334,500
3.2700 3.3600 3.2700 3.3000 2,460,900
Weekend
Weekend
3.3300 3.4100 3.2600 3.2700 2,704,700
3.3200 3.3450 3.2500 3.2900 2,563,000
3.3500 3.4250 3.2910 3.3500 3,069,900
3.4600 3.5500 3.3400 3.3600 3,588,400
No trading
Weekend
Weekend
3.2800 3.4300 3.2500 3.4200 4,867,100
3.3000 3.3200 3.1900 3.2300 2,550,400
3.1000 3.3400 3.1000 3.2800 7,470,000
3.0700 3.0950 3.0200 3.0900 2,355,200
3.0800 3.1350 3.0600 3.1100 2,216,400
Weekend
Weekend
3.2100 3.2300 3.0600 3.1100 3,188,500
3.1900 3.2500 3.1300 3.2400 2,276,800
3.2000 3.2000 3.0900 3.1500 4,046,200
3.1400 3.2250 3.1100 3.2000 3,814,600
3.1300 3.1300 3.0250 3.1100 2,715,900
Weekend
Weekend
2.9800 3.2400 2.9500 3.1100 6,148,000
3.0700 3.0800 2.9200 2.9500 4,681,400
3.0400 3.2000 3.0050 3.1200 10,824,100
2.9900 3.0300 2.9600 2.9700 2,472,100
2.9400 3.0200 2.9000 3.0000 4,056,900
Weekend
Weekend
2.9500 2.9700 2.8600 2.9400 3,074,000
2.9500 2.9600 2.8400 2.8800 4,109,000
26 · 10-Q After-hours · 16:04 ET 10-Q ↗
3.0500 3.2000 2.9200 2.9300 6,045,800
25 · 8-K Pre-market · 07:33 ET 8-K ↗
3.0600 3.0800 2.9800 3.0000 3,634,600
3.0900 3.1000 2.9900 3.0500 5,260,500
Weekend
Weekend
3.0500 3.1000 3.0000 3.0800 4,506,100
3.0300 3.0500 2.9500 3.0100 3,977,300
3.0700 3.1200 3.0050 3.0300 3,164,000
3.0100 3.0800 2.9500 3.0700 8,163,000
2.8820 3.0250 2.8550 3.0000 4,647,300
Weekend
Weekend
2.9900 2.9900 2.7800 2.8400 3,892,100
2.9250 3.0050 2.8600 2.9800 5,437,200
3.0000 3.1000 2.8950 2.9200 8,295,600
3.1620 3.3100 2.8150 2.9900 17,142,600
24 · 8-K Pre-market · 07:04 ET 8-K ↗
2.8000 3.0300 2.8000 2.9600 4,059,600
Weekend
Weekend
2.8500 2.8890 2.7600 2.7700 1,911,600
2.7900 2.8400 2.7500 2.8400 1,625,800
2.8100 2.8650 2.7650 2.8100 2,290,500
2.8100 2.8700 2.7800 2.8200 1,984,600
2.8900 2.9100 2.7900 2.8100 2,614,500
Weekend
Weekend
2.7900 2.9500 2.7700 2.8700 2,963,800
2.9600 2.9740 2.8100 2.8500 2,995,400
2.9400 3.0000 2.8850 2.9800 2,862,400
2.9800 3.0150 2.9000 2.9300 3,299,000
3.0100 3.0200 2.9200 2.9900 2,457,100
Weekend
Weekend
3.1200 3.1350 2.9500 3.0500 2,992,900
3.1100 3.1490 3.0410 3.1200 2,877,000
2.9400 3.1100 2.9300 3.1100 3,520,300
3.0800 3.1200 2.9600 3.0200 4,619,800
3.2500 3.3000 3.0800 3.0800 4,348,100
Weekend
Weekend
No trading
3.1800 3.2600 3.1000 3.1600 4,055,500
3.0200 3.4000 3.0000 3.1500 7,976,000
2.9500 3.1400 2.9140 3.0400 4,332,500
2.8500 2.9400 2.7900 2.9400 3,638,900
Weekend
Weekend
2.8500 2.9040 2.7400 2.8200 17,105,400
2.9600 2.9950 2.8600 2.8700 2,781,400
2.9200 3.0400 2.9200 2.9500 3,494,100
2.8800 3.0400 2.8750 2.9100 4,223,900
2.8400 3.0450 2.8300 2.9300 5,776,500
Weekend
Weekend
No trading
2.6800 2.7700 2.6800 2.7000 11,688,200
2.6500 2.7100 2.6200 2.6400 3,570,900
23 · 8-K After-hours · 16:05 ET FORM 8-K ↗
2.6400 2.6800 2.6000 2.6200 2,907,200
2.6200 2.6760 2.5800 2.6400 3,516,900
Weekend
Weekend
2.6100 2.6600 2.5820 2.6100 2,142,300
2.6150 2.6450 2.5700 2.5900 3,425,300
2.6200 2.7050 2.6050 2.6100 3,042,400
2.7660 2.8000 2.6200 2.6600 3,352,800
2.7500 2.7800 2.6800 2.7300 2,172,800
Weekend
Weekend
2.9200 2.9200 2.6850 2.7100 3,129,200
2.8400 2.9950 2.8400 2.9200 2,818,700
2.9300 2.9500 2.8400 2.8700 3,033,300
2.9900 3.0000 2.8950 2.9000 3,144,500
3.0200 3.0450 2.9300 3.0100 2,294,400
Weekend
Weekend
3.0700 3.0950 3.0200 3.0500 2,594,100
2.9800 3.1300 2.9800 3.0700 3,932,800
2.9900 3.0300 2.9600 2.9800 2,587,800
2.9000 3.0000 2.8940 2.9300 2,154,100
No trading
Weekend
Weekend
2.9400 3.0000 2.8800 2.9000 1,988,600
2.8000 2.9300 2.7700 2.9300 3,062,800
2.7500 2.8490 2.7300 2.8200 2,229,200
2.8000 2.8400 2.7300 2.7400 2,514,300
2.8500 2.8900 2.7200 2.8000 3,462,100
Weekend
Weekend
2.9000 2.9380 2.8100 2.8500 2,286,900
3.0100 3.0290 2.9040 2.9200 2,388,400
22 · 10-Q After-hours · 16:13 ET 10-Q ↗
2.9800 3.0400 2.8900 3.0200 3,584,600
21 · 8-K Pre-market · 07:34 ET 8-K ↗
3.0800 3.1050 3.0050 3.0800 2,436,600
3.0900 3.2200 3.0600 3.0900 2,937,200
Weekend
Weekend
3.0700 3.1100 3.0100 3.0900 2,858,200
3.2200 3.2400 2.9950 3.0400 3,720,500
3.0600 3.2600 3.0400 3.2600 4,096,700
3.0800 3.1500 3.0000 3.0600 3,470,400
2.8400 3.0400 2.8400 3.0200 5,175,700
Weekend
Weekend
2.5900 2.8200 2.5600 2.8200 4,956,800
2.6600 2.6750 2.5750 2.6000 5,675,500
2.7100 2.7300 2.6000 2.6300 4,888,600
2.7800 2.8500 2.7200 2.7400 4,870,600
2.8600 2.9050 2.7500 2.8000 5,894,900
Weekend
Weekend
20 · 8-K After-hours · 16:05 ET FORM 8-K ↗
2.9500 3.0100 2.8200 2.8500 14,733,700
19 · 424B5 Next filing day · accepted 23 Apr, 21:29 ET 424B5 ↗
3.0750 3.1600 2.8000 2.8900 30,489,000
18 · 424B5 After-hours · 17:24 ET 424B5 ↗ 17 · S-3MEF After-hours · 21:15 ET S-3MEF ↗
3.4500 3.5100 3.4150 3.4700 2,948,100
3.5600 3.6400 3.3900 3.4100 3,251,000
3.4500 3.5800 3.3900 3.5600 2,161,600
Weekend
Weekend
3.5500 3.5970 3.4200 3.5000 2,868,800
16 · 8-K After-hours · 17:07 ET 8-K ↗
3.4000 3.5500 3.3500 3.5100 2,580,500
3.3300 3.4200 3.2850 3.4000 2,080,100
3.2500 3.3200 3.2300 3.2900 1,991,000
3.2300 3.2800 3.1800 3.2300 2,122,600
Weekend
Weekend
3.3900 3.4100 3.2200 3.2400 1,936,600
3.3500 3.4400 3.3100 3.3800 1,989,200
3.4800 3.5400 3.3550 3.3700 1,695,700
3.3400 3.4500 3.2550 3.3800 2,039,600
3.3400 3.4800 3.3000 3.3300 2,360,600
Weekend
Weekend
No trading
3.1000 3.3450 3.0700 3.3400 2,737,000
3.1400 3.2300 3.1000 3.1200 2,111,700
2.9800 3.1200 2.9500 3.0800 3,290,500
3.0300 3.0300 2.8700 2.8800 3,116,300
Weekend
Weekend
3.1600 3.1900 3.0200 3.0200 2,674,900
3.2600 3.3300 3.1900 3.2000 2,194,800
3.3000 3.3850 3.2350 3.3100 4,369,500
3.3700 3.4100 3.2300 3.2400 3,345,400
3.4000 3.5300 3.3100 3.4400 3,449,300
Weekend
Weekend
3.4300 3.5200 3.3100 3.3400 12,523,700
3.3800 3.5100 3.3400 3.4200 2,686,800
3.5000 3.5200 3.3600 3.4200 3,477,100
3.6300 3.7100 3.5150 3.5300 2,531,600
15 · DEF 14A Pre-market · 07:05 ET DEF 14A ↗
3.6000 3.6800 3.5400 3.6200 2,650,200
Weekend
Weekend
3.6200 3.6800 3.4700 3.5000 3,119,100
3.7700 3.7700 3.5800 3.6000 2,959,400
3.8900 3.9100 3.7400 3.8000 2,889,500
3.9000 4.0400 3.8300 3.8600 3,565,700
3.6400 3.8900 3.6100 3.8800 5,337,000
Weekend
Weekend
3.5400 3.7450 3.4150 3.5400 5,385,400
14 · PRE 14A Pre-market · 08:01 ET PRE 14A ↗ 13 · 10-K Pre-market · 07:56 ET 10-K ↗
4.1000 4.2000 3.5000 3.5050 7,710,000
12 · 8-K Pre-market · 07:08 ET 8-K ↗
4.1900 4.3500 4.1260 4.2700 2,267,300
4.0500 4.2600 4.0400 4.1600 2,863,800
4.2400 4.2700 4.1500 4.1600 2,388,500
Weekend
Weekend
4.4000 4.4700 4.2900 4.3100 3,018,500
4.5600 4.5900 4.3800 4.4600 1,902,900
4.5900 4.6100 4.4900 4.5600 2,056,100
4.5200 4.8300 4.5200 4.5700 2,978,900
4.3400 4.6400 4.3400 4.5200 3,179,200
Weekend
Weekend
4.4900 4.5100 4.3600 4.3800 4,136,600
4.4700 4.5300 4.2700 4.4900 3,275,400
4.5000 4.5500 4.4150 4.4600 2,829,100
4.5400 4.6400 4.4800 4.5000 1,885,400
No trading
Weekend
Weekend
4.6200 4.7500 4.5300 4.5300 3,888,000
4.6500 4.7000 4.4700 4.5700 2,236,600
4.7200 4.7450 4.5400 4.6300 1,867,000
4.7000 4.8300 4.6200 4.6500 2,140,700
4.8500 4.9600 4.6500 4.6900 3,722,800
Weekend
Weekend
5.0000 5.0850 4.8400 4.8700 3,846,000
5.0900 5.2800 4.8800 4.9200 3,972,600
5.4700 5.5300 5.0850 5.1300 3,557,500
11 · 8-K After-hours · 16:05 ET 8-K ↗
5.5450 5.6400 5.2050 5.4700 4,565,900
5.5600 5.7500 5.2600 5.5500 5,175,800
Weekend
Weekend
5.0500 5.6550 5.0300 5.6000 6,280,800
5.2200 5.4900 5.0300 5.1000 4,089,500
10 · 8-K After-hours · 17:26 ET 8-K ↗ 9 · 424B5 After-hours · 17:23 ET 424B5 ↗
5.9300 6.3600 5.0400 5.1200 13,080,000
5.6400 6.2200 5.6000 6.1800 5,788,700
5.5000 5.6900 5.1900 5.6600 5,736,700
Weekend
Weekend
5.4000 6.4400 5.3410 5.5000 15,507,200
4.6500 5.4000 4.6500 5.3800 8,195,000
4.2500 4.6250 4.1900 4.6200 3,909,200
4.1000 4.2600 4.0300 4.2300 4,516,600
No trading
Weekend
Weekend
4.3000 4.3700 4.1700 4.2400 2,598,200
4.1500 4.4000 4.0500 4.2400 4,554,000
4.0000 4.2050 3.9800 4.1800 3,266,500
4.0400 4.0950 3.9600 4.0100 2,604,200
4.0800 4.1250 4.0000 4.0500 2,763,800
Weekend
Weekend
4.1200 4.1800 3.9850 4.0200 3,075,200
4.1500 4.2170 4.0200 4.0800 3,843,100
4.0000 4.3600 3.9800 4.1900 7,287,300
4.0820 4.1800 3.8600 3.9600 5,650,600
4.0950 4.5300 3.9600 4.0900 27,007,100
Weekend
Weekend
3.6200 3.6600 3.4800 3.5100 3,567,400
No trading
3.6000 3.6250 3.5200 3.6100 4,293,100
3.6800 3.7200 3.6000 3.6100 3,158,400
3.8400 3.8400 3.6500 3.6800 4,528,500
Weekend
Weekend
3.9700 3.9900 3.8400 3.8600 2,924,300
No trading
4.0500 4.1100 3.9700 3.9800 2,079,900
4.1000 4.1600 3.9800 4.0000 4,440,900
3.9600 4.4500 3.9500 4.1400 6,879,400
Weekend
Weekend
4.5800 4.5900 3.8300 3.9000 22,528,400
8 · 8-K Pre-market · 06:30 ET FORM 8-K ↗
5.2300 5.2800 5.0200 5.0500 2,860,200
5.0250 5.3650 5.0200 5.0900 2,877,200
5.2200 5.2750 4.9200 5.0300 4,613,800
5.2900 5.5000 5.1700 5.2800 3,707,900
Weekend
Weekend
5.3950 6.0300 5.2500 5.2700 6,381,900
5.4000 5.6300 5.3100 5.3400 2,785,800
5.4900 5.5600 5.3550 5.4300 3,354,500
5.6900 5.8300 5.3650 5.5200 4,808,200
5.3500 5.7400 5.0250 5.6100 5,549,200
Weekend
Weekend
5.3100 5.4400 5.1900 5.2400 2,583,800
5.0900 5.4600 5.0000 5.3100 3,112,700
4.8200 5.1500 4.7000 5.1100 2,566,400
5.0000 5.0000 4.7500 4.7600 3,021,000
5.0800 5.1150 4.7300 4.9300 4,393,600
7 · 8-K Pre-market · 08:00 ET FORM 8-K ↗
Weekend
Weekend
5.2100 5.3300 5.1500 5.2600 2,119,800
No trading
5.1100 5.3100 5.1000 5.1700 2,561,300
5.1000 5.2500 4.9800 5.1400 3,326,100
4.8250 5.1900 4.7960 5.1000 4,683,600
Weekend
Weekend
4.4600 4.8800 4.4400 4.8100 3,481,400
4.6700 4.7050 4.4000 4.4700 2,995,100
4.5400 4.7500 4.5100 4.5900 4,030,800
4.1600 4.7290 4.0910 4.6500 4,334,200
4.1400 4.2190 4.0700 4.1900 2,313,700
Weekend
Weekend
3.9500 4.2250 3.9500 4.1700 2,628,400
6 · S-3/A After-hours · 17:26 ET S-3/A ↗
4.1800 4.2160 4.0300 4.0600 2,434,000
4.3000 4.3500 4.1150 4.2300 2,374,100
4.2600 4.3100 4.1400 4.2800 2,977,000
4.2000 4.3600 4.0600 4.2600 6,038,100
Weekend
Weekend
3.9200 4.1600 3.7750 4.1100 4,258,000
5 · S-3 After-hours · 16:47 ET S-3 ↗ 4 · 8-K After-hours · 16:30 ET 8-K ↗ 3 · 424B5 After-hours · 16:25 ET 424B5 ↗ 2 · 10-Q After-hours · 16:10 ET 10-Q ↗
3.8200 4.1150 3.7600 3.9400 4,248,600
1 · 8-K Pre-market · 07:04 ET 8-K ↗
3.7500 3.8300 3.7300 3.7500 2,647,500
3.8900 3.9800 3.7400 3.7600 3,175,000
4.0300 4.0500 3.9250 3.9600 2,188,900
Weekend
Weekend
4.2500 4.2500 3.9900 4.0500 2,447,400
4.0500 4.2500 4.0200 4.0700 4,023,700
4.0600 4.0700 3.9300 4.0000 2,310,200
4.1500 4.1500 4.0400 4.0600 1,746,300
3.9900 4.1500 3.9900 4.1400 2,921,900
Weekend
Weekend
4.0000 4.1000 3.9400 3.9500 1,931,900

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.

27 8-K 8-K (opens SEC filing in a new tab) After market open · 11:03 ET Summarise
26 10-Q 10-Q (opens SEC filing in a new tab) After-hours · 16:04 ET Summarise
25 8-K 8-K (opens SEC filing in a new tab) Pre-market · 07:33 ET Summarise
24 8-K 8-K (opens SEC filing in a new tab) Pre-market · 07:04 ET Summarise
23 8-K FORM 8-K (opens SEC filing in a new tab) After-hours · 16:05 ET Summarise
22 10-Q 10-Q (opens SEC filing in a new tab) After-hours · 16:13 ET Summarise
21 8-K 8-K (opens SEC filing in a new tab) Pre-market · 07:34 ET Summarise
20 8-K FORM 8-K (opens SEC filing in a new tab) After-hours · 16:05 ET Summarise
19 424B5 424B5 (opens SEC filing in a new tab) Next filing day · accepted 23 Apr, 21:29 ET Summarise
18 424B5 424B5 (opens SEC filing in a new tab) After-hours · 17:24 ET Summarise
17 S-3MEF S-3MEF (opens SEC filing in a new tab) After-hours · 21:15 ET Summarise
16 8-K 8-K (opens SEC filing in a new tab) After-hours · 17:07 ET Summarise
15 DEF 14A DEF 14A (opens SEC filing in a new tab) Pre-market · 07:05 ET Summarise
14 PRE 14A PRE 14A (opens SEC filing in a new tab) Pre-market · 08:01 ET Summarise
13 10-K 10-K (opens SEC filing in a new tab) Pre-market · 07:56 ET Summarise
12 8-K 8-K (opens SEC filing in a new tab) Pre-market · 07:08 ET Summarise
11 8-K 8-K (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 · 17:26 ET Summarise
9 424B5 424B5 (opens SEC filing in a new tab) After-hours · 17:23 ET Summarise
8 8-K FORM 8-K (opens SEC filing in a new tab) Pre-market · 06:30 ET Summarise
7 8-K FORM 8-K (opens SEC filing in a new tab) Pre-market · 08:00 ET Summarise
6 S-3/A S-3/A (opens SEC filing in a new tab) After-hours · 17:26 ET Summarise
5 S-3 S-3 (opens SEC filing in a new tab) After-hours · 16:47 ET Summarise
4 8-K 8-K (opens SEC filing in a new tab) After-hours · 16:30 ET Summarise
3 424B5 424B5 (opens SEC filing in a new tab) After-hours · 16:25 ET Summarise
2 10-Q 10-Q (opens SEC filing in a new tab) After-hours · 16:10 ET Summarise
1 8-K 8-K (opens SEC filing in a new tab) Pre-market · 07:04 ET Summarise